Each month, The Dynasty Guru will provide a prospect update that includes notable performances (good and bad), assignments, promotions, trades, injuries, and suspensions. Most importantly, the monthly update will examine prospects with increasing and decreasing fantasy value, from the elite to the obscure.

At the beginning of August, TDG reviewed July performances for infielders, outfielders, and pitchers. In addition, TDG updated the Top 240 Fantasy Prospects. Since then, several notable prospects exceeded rookie limits and others arrived in the majors. As this update only reviews performances for one month, please note this bright, flashing warning: SMALL SAMPLE SIZE!

Notable Catcher Prospect Performances

The Major League Catcher Prospect

Danny Jansen, Toronto Blue Jays. In mid-August, the Blue Jays promoted Jansen to the majors. Since then, he received nearly regular playing time, impressing at the plate (.333/.419/.556). Jansen is a potentially above-average hitter with average power. Such a player is rare at catcher. Very clearly the future for the Blue Jays, Jansen is a top-10 dynasty fantasy catcher.

Others of Note:

• Tomas Nido, New York Mets
• Willians Astudillo, Minnesota Twins
• Aramis Garcia, San Francisco Giants

The Good

Francisco Mejia, San Diego Padres. A slow start to the season is far in the rear-view mirror for Mejia. Although July provided a brief dip in performance, marked by a mid-month trade, he rebounded strongly in August. Over his last 14 games in August, Mejia has hits in all but two, including four home runs (18-for-59). Further, he is already 6-for-10 with 2 home runs in September! In just 30 games since joining the Padres, Mejia has as many home runs (7) in 49 less games (.322/.359/.576).

Jake Rogers, Detroit Tigers. In his first 24 games this year, Rogers had 0 extra base hits (.161/.237/.161)! As the weather warmed, so did he. Since the beginning of June, Rogers has 14 home runs (.257/.347/.533). Meanwhile, he remains an excellent defensive catcher with a cannon arm. Indeed, Rogers has thrown out 50 of 90 base stealers (55.6%)! Although he is unlikely to hit for a high average, he has solid power and a high floor as a very likely major league contributor. In two-catcher leagues, Rogers is a must-own prospect. In more shallow leagues, he is an intriguing bat at a shallow position.

Max Pentecost, Toronto Blue Jays. The 10th pick in the 2014 MLB Draft, Pentecost has had a long, injury-riddled journey through the minors. A well-regarded bat, he has failed to live up to expectations. This past month, Pentecost provided a glimpse of his potential, hitting .375/.381/.650 with 6 home runs. Already 25 years old, he likely is running out of opportunities.

Others of Note:

• Keibert Ruiz, Los Angeles Dodgers (.341/.376/.484)
• M.J. Melendez, Kansas City Royals (.299/.386/.546)
• Cal Raleigh, Seattle Mariners (.301/.377/.591 with 6 home runs)
• Blake Hunt, San Diego Padres (.316/.378/.506)
• Yermin Mercedes, Chicago White Sox (.330/.375/.591 with 6 home runs)

The Bad

Zack Collins, Chicago White Sox. Collins is the prototypical three-true-outcomes prospect. On the year, he has walked or struck out in 48.9% of plate appearances! Unfortunately, Collins lately has leaned heavily on the least favorable outcome: strikeouts (33% in August).

Will Smith, Los Angeles Dodgers. The Dodgers promoted Smith to Triple-A at the beginning of the month following his incredible power surge in June and July (15 home runs). Since arriving in Triple-A, however, he is struggling (.155/.225/.211) with 31 strikeouts (38.8%).

Tyler Stephenson, Cincinnati Reds. Like Pentecost, Stephenson is a former first round pick who is finally healthy. In addition, he will need his bat  to carry him as he is a mediocre defender with a terrible caught stealing percentage (24.8%) despite a strong arm. Although Stephenson has had a decent season (.250/.338/.392), he has struggled of late (6-for-50).

Additional Catcher Prospect Notes

• Sean Murphy returned to action from a broken right hamate bone in late-August.
• The Braves promoted William Contreras to High-A at the beginning of August.
• Luis Campusano missed the entire month due to a concussion.
• In early August, the Marlins aggressively promoted Will Banfield to Low-A.
• Notable AFL Participants: Daulton Varsho, Keibert Ruiz, Austin Allen, Jake Rogers, and Meibrys Viloria.

Notable First Base Prospect Performances

The Major League First Base Prospect

Ryan O’Hearn, Kansas City Royals. Last year, the Royals demoted O’Hearn from Triple-A to make room for players on rehab assignment, and then left him unprotected in the Rule 5 draft this fall. Such little recent faith within the organization is disconcerting. Nonetheless, the last place Royals have nothing to play for the rest of the year so O’Hearn has received an extended look. So far, he is showing off his power stroke with 7 home runs over his first 21 games (.257/.333/.600). Ultimately, he likely is a platoon bat with 40/45 hit tool and 50/55 game power.

Others of Note:

• Christian Walker, Arizona Diamondbacks

The Good

Peter Alonso, New York Mets. Since his promotion to Triple-A in June, Alonso’s performance slowed significantly. This past month, however, he put on quite a power displaying, blasting 11 home runs (.308/.392/.731). Despite his recent success, the Mets announced Alonso will not receive a promotion to the majors this year. In fact, he will head to the Arizona Fall League in October. Expect Alonso to debut in the majors early next year.

Evan White, Seattle Mariners. A first round pick in the 2017 MLB Draft, White has spent the entire season in High-A. Up until this past month, his performance was unspectacular for an advanced college bat (.282/.349/.394). In August, White finally discovered his power stroke, with 18 extra base hits (.363/.454/.703), nearly doubling his season total.

Ibandel Isabel, Cincinnati Reds. This year, Isabel quietly amassed 36 home runs. A streaky prospect, he previously featured in the monthly update after stringing together 10 home runs over a 10-game stretch in June. In August, Isabel once more mashed 12 home runs (.296/.355/.704). On the downside, his massive, 70-grade (or better) raw power continues to come with tons of strikeouts, including 37 this month and 161 this year (36.2%).

Others of Note:

• Nick Pratto, Kansas City Royals (.358/.430/.575)
• Tyler Nevin, Colorado Rockies (.359/.432/.544)
• Tyreque Reed, Texas Rangers (.316/.398/.632 with 7 home runs)
• Frank Schwindel, Kansas City Royals (.316/.365/.556)
• Matt Winaker, New York Mets (.319/.418/.638 with 7 home runs)

The Bad

Josh Naylor, San Diego Padres. Since his blazing first 25 games (.380/.457/.690 with 8 home runs), Naylor has hit just .274/.362/.379 with 9 home runs. The power outage is extremely concerning. Given his defensive shortcomings, Naylor will need to hit to succeed. At this point, his offensive profile is strikingly similar to Dominic Smith.

Brent Rooker, Minnesota Twins. Two straight months slashing .300/.400/.600 turned around Rooker’s disappointing season, raising his season line as high as .280/.345/.523. The hot hitting came to an end in August (.152/.282/.261).

Mason Martin, Pittsburgh Pirates. Last year, Martin impressed during his professional debut in the Gulf Coast League (.307/.457/.630). His performance was so encouraging, the Pirates aggressively assigned him to Low-A to start the season. Martin started so poorly this year, the Pirates demoted him to the Appalachian League. After a strong start there, he fell off significantly in August (.130/.292/.304 with 46 strikeouts).

Additional First Base Prospect Notes

• In early August, the Rays promoted Nathaniel Lowe to Triple-A.
• The Blue Jays promoted Chad Spanberger to High-A.
• The Twins acquired Ryan Costello in the Zach Duke trade.
• Notable AFL Participants: Peter Alonso, Brent Rooker, Evan White, Pavin Smith, and Josh Ockimey.

Notable Second Base Prospect Performances

The Major League Second Base Prospect

The Graduate: David Bote, Chicago Cubs. With two walk-off home runs this summer, Bote is making a lot of noise in his debut. However, he only possesses borderline average hit and power tools with no clear path to long-term playing time in a crowded Cubs infield. Ultimately, Bote is a solid utility infielder who may occasionally run into periods of fantasy relevance with regular playing time.

Luis Urias, San Diego Padres. In August, Urias was nearly an impossible out, hitting .420/.480/.659 with 15 extra-base hits. As such, the Padres finally promoted him to the majors. Over his first four games, Urias knocked a 343-foot home run down the right field line and stole a base. Although this power/speed performance is unlikely to continue, he is a potentially elite hitter with enough pop to develop into a solid fantasy performer.

Brandon Lowe, Tampa Bay Rays. In early-August, the Rays promoted Lowe to the majors after a dominant performance in Triple-A (.304/.380/.613). Following his promotion, he went 0-for-19 with 7 strikeouts in his first 6 games. Since then, Lowe has been excellent, going 15-for-42 with 3 home runs and 2 stolen bases. Owners who patiently rode out his initial struggles are reaping the benefits (including yours truly!).

Jeff McNeil, New York Mets. One of the top minor league performers this year, McNeil continues to hit in the majors (.319/.386/.471). Further, he is impressing in the field, with good range and just one error in his first 30 games at second base. Lazy comparison: former Met, Daniel Murphy.

Others of Note:

• Dawel Lugo, Detroit Tigers

The Good

Cavan Biggio, Toronto Blue Jays. This year, Biggio exploded onto the prospect scene, hitting .307/.431/.645 with 13 home runs through his first 50 games. Since then, he slowed dramatically, hitting just .195 and .181 in June and July, respectively. Last month, Biggio rebounded, displaying power, speed, and patience (.274/.388/.504 with 5 home runs and 8 stolen bases). Although he is unlikely to hit for a high batting average, he should provide defensive versatility, power, and patience. Along with Guerrero Jr. and Bichette, Biggio is heading to the Arizona Fall League in October.

Vidal Brujan, Tampa Bay Rays. Listed at a diminutive 5’9″ and 155 pounds, Brujan muscled up in August. After going 6-for-10 with a home run in Low-A, the Rays promoted him to High-A Florida State League. There, Brujan went on an absolute tear, hitting .371/.462/.629 with 4 more home runs and 12 stolen bases. On the year, he is now up to 9 home runs and 55 stolen bases. With plus speed, an excellent hit tool, and some pop, Brujan is a rising prospect.

Bret Boswell, Colorado Rockies. Few prospects have enjoyed the same hitter-friendly confines as Boswell. Playing in Asheville and Lancaster is a hitting prospect’s dream. In fact, he hit .308/.343/.554 in Asheville and .368/.424/.789 so far in Lancaster! Regardless, Boswell is an intriguing power prospect at second base for the Rockies so he deserves our attention. This past month, he destroyed California League pitching, slashing .327/.397/.693 with 10 home runs. Despite the impressive numbers, Boswell also struck out 36 times (31%) and is nearly 24 years old.

Others of Note:

• Garrett Hampson, Colorado Rockies (.333/.413/.485)
• Nick Solak, Tampa Bay Rays (.305/.404/.537)
• Kevin Kramer, Pittsburgh Pirates (.356/.398/.525)
• Luis Arraez, Minnesota Twins (.346/.393/.444)
• Luis Santana, New York Mets (.338/.427/.507)

The Bad

Keston Hiura, Milwaukee Brewers. Even excellent hitters occasionally struggle. In August, Hiura went hitless in 11 games and slashed just .207/.263/.348. Since arriving in Double-A, he has been solid, but unspectacular (.268/.330/.416). With only average speed and power, Hiura will need to hit a ton to make good on his elite prospect pedigree.

Isan Diaz, Miami Marlins. The Marlins acquired Diaz in the Christian Yelich trade last offseason. Like other top Marlins prospects, he has received aggressive promotions this year. Since mid-July, Diaz has been in Triple-A at just 22 years old. Still a raw, three-true-outcomes hitter, he has understandably struggled at times this year, including last month (.198/.261/.327 with 31 strikeouts).

Max Schrock, St. Louis Cardinals. On May 5th, Schrock was hitting .348/.397/.446 in Triple-A. At the time, he looked the part of a potential plus hitter with modest power. Some even argued Schrock was a better prospect than Luis Urias! Since then, his performance and value steadily plummeted, including an unsightly .200/.262/.236 line in August.

Additional Second Base Prospect Notes

• The Tigers promoted Kody Clemens, the son of Roger Clemens and a third round pick in the 2018 MLB Draft, to High-A.
• The Marlins acquired Bryson Brigman from the Mariners for Cameron Maybin.
• Notable AFL Participants: Keston Hiura, Jahmai Jones, Shed Long, Cavan Biggio, and Nico Hoerner.

Notable Third Base Prospect Performances

The Major League Third Base Prospect

Taylor Ward, Los Angeles Angels. This year, the Angels moved Ward from catcher to third base. Possibly due to the defensive switch, his bat finally came to life. Between Double- and Triple-A, Ward slashed .349/.446/.531, displaying legitimate power, patience, and tons of line drives (25%). In mid-August, the Angels promoted him to the majors, and he has received regular playing time at third base. In many fantasy leagues, Ward inexplicably still has catcher eligibility. An everyday player eligible at catcher is fantasy gold for counting stats.

The Graduates:

• Renato Nunez, Baltimore Orioles
• Brandon Dixon, Cincinnati Reds

The Good

Austin Riley, Atlanta Braves. At just 21 years old, Riley is one of the youngest players in the International League. Understandably, he has struggled at times in Triple-A, including an atrocious 0-for-5 with 5 strikeouts on August 9th. On August 21st, however, Riley homered in both games of a double-header, turning his month around. Over the next ten days, he added 5 more home runs.

Colton Welker, Colorado Rockies. From July 12th to August 10th, Welker enjoyed a 20-game hitting streak, including 6-straight multi-hit games. In fact, in August, he only has two hitless games, while slashing .413/.446/.575. Despite his success, Welker has spent the entire year in a hitter-friendly environment at Lancaster. There, he has hit .376/.419/.572, with underwhelming power numbers on the year.

Michael Chavis, Boston Red Sox. Chavis missed half the season due to suspension. Upon his return in July, he struggled to regain his 2017 form, hitting just .152/.264/.326. In August, Chavis dominated, slashing .395/.465/.618 in Double-A. Consequently, the Red Sox promoted him to Triple-A, where he kept mashing (.360/.385/.720 over his first 6 games).

Others of Note:

• Vladimir Guerrero Jr., Toronto Blue Jays (.333/.409/.552)
• Mark Vientos, New York Mets (.309/.442/.485)
• Cristian Santana, Los Angeles Dodgers (.365/.393/.643 with 8 home runs)
• Jhoan Urena, New York Mets (.277/.371/.566 with 7 home runs)
• Jomar Reyes, Baltimore Orioles (.346/.386/.577)

The Bad

Hudson Potts, San Diego Padres. The Padres promoted Potts to Double-A at just 19 years old. Still a raw prospect, he has struggled in his first taste of the upper minors (.176/.282/.265 with 28 strikeouts).

Lucas Erceg, Milwaukee Brewers. Erceg is one of the streakiest hitters in the minors. Unfortunately, he ended the season mired in a 3-for-35 slump.

Additional Third Base Prospect Notes

• In late July, the Cardinals aggressively promoted Nolan Gorman to Low-A. There, he continues to hit for power (6 home runs), but is struggling with contact (35 strikeouts).
• In addition, the Cardinals promoted fellow third base prospect Elehuris Montero to High-A.
• The Rangers acquired Sherten Apostel from the Pirates.
• Notable AFL Participants: Vladimir Guerrero Jr., Michael Chavis, Hudson Potts, and Bobby Dalbec.

Notable Shortstop Prospect Performances

The Major League Shortstop Prospect

Kevin Newman, Pittsburgh Pirates. This year, Newman rehabilitated his fledgling prospect status with a solid performance in Triple-A. In fact, after a poor April, he was excellent the rest of the year, hitting .317/.370/.428 with 26 stolen bases. Still, Newman provides little power. Should he retain his newfound aggression on the bases, he could carve out value similar to Jose Peraza. Otherwise, Newman is an uninspiring fantasy prospect.

Others of Note:

• Jose Rondon, Chicago White Sox

The Good

Willi Castro, Detroit Tigers. At the trade deadline, the Tigers acquired Castro from the Indians for Leonys Martin. The trade was a complete coup for the Tigers as Martin is now out for the year and Castro has been on fire since joining the organization. Indeed, he was so good at Double-A (.324/.366/.562), he received a promotion to Triple-A at the end of the month. Just 21 years old, Castro is on the cusp of the majors.

Adam Hall, Baltimore Orioles. Hall is a second round pick in the 2017 MLB Draft out of Canada. Entering the draft, he received little fan fare as a speedster with little power and questionable defense. Following the draft, an oblique injury limited him to just two games. Held back in extended spring training this year, Hall received an assignment to the New York-Penn League in June. This past month, he had a 19-game hitting streak and stole 15 bases in 14 games (.390/.462/.524). Still a raw prospect, Hall has intriguing upside if he taps into more power as he physically matures.

Luis Garcia, Philadelphia Phillies. Do not confuse this Luis Garica with the Nationals’ star prospect or the Phillies’ reliever by the same name. A top 2017 J2 signee, Garcia netted a $2.5 million bonus on the basis of his excellent hit tool, plus speed, and promising defense. This year, he hit .369/.433/.488 at just 17 years old in the Gulf Coast League.

Others of Note:

• Bo Bichette, Toronto Blue Jays (.339/.402/.475)
• Wander Franco, Tampa Bay Rays (.346/.433/.548)
• Gavin Lux, Los Angeles Dodgers (.320/.411/.485)
• Jazz Chisholm, Arizona Diamondbacks (.337/.366/.516 with 9 stolen bases)
• Tyler Freeman, Cleveland Indians (.330/.387/.500 with 7 stolen bases)
• Gabriel Arias, San Diego Padres (.286/.353/.562)
• Owen Miller, San Diego Padres (.362/.390/.543)

The Bad

Brendan Rodgers, Colorado Rockies. In early-August, the Rockies promoted Rodgers to Triple-A, where he slashed just .232/.264/.290. Given the dominance of Trevor Story, the Rockies can afford to be patient with Rodgers. Further, Garrett Hampson likely will receive the first opportunity at second base should the Rockies fail to re-sign D.J. LeMahieu. As such, Rodgers likely will spend the beginning of next year in Triple-A.

Nick Gordon, Minnesota Twins. After a promising first two weeks in Triple-A (.357/.379/.464), Gordon has struggled the rest of the season. In fact, he has failed to crack the Mendoza Line (.200) in any month following his strong start. Early season rumblings for Gordon’s promotion to the majors are now a faint and distant whisper. Expect him to repeat the level to start next year (as he did this year with Double-A).

Additional Shortstop Prospect Notes

• Oneil Cruz missed half the month with a groin strain.
• The Padres promoted Xavier Edwards to the Northwest League, where he has 10 stolen bases in his first 19 games.
• The Mets promoted 17-year-old Ronny Mauricio to the Appalachian League, where he joins fellow top 2017 J2 signee Wander Franco.
• The Giants acquired Abiatal Avelino from the Yankees for Andrew McCutchen.
• Other notable promotions: Wenceel Perez and Osiris Johnson to Low-A.
• Notable AFL Participants: Brendan Rodgers, Bo Bichette, Carter Kieboom, Andres Gimenez, Jazz Chisholm, Cole Tucker, Yu Chang, and Lucius Fox.

Please feel free to post comments, questions, or your own observations!

On Wednesday, the Monthly Prospect Update will explore outfield prospects. Stay tuned!

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