With Maikel Franco’s arrival over the weekend, 24 of Baseball America’s 2015 top 100 prospects have played in the major leagues already. If you want a better indicator for our game, 18 of Bret’s top 101 dynasty league prospects for 2015 have sported big league duds. Prospects are being called on more quickly and at a higher rate than ever and because we’re humans, we have a tendency to disproportionately focus on the the most recent ones. Sure, Lance McCullers is going to pitch today and that is exciting but Archie Bradley also returned from a line drive to the head on Saturday and I heard relatively little about that by comparison, despite Bradley being the better prospect by a wide margin.

We also tend to place less focus on down-list prospects unless they force our hands with production you can’t ignore (think Devon Travis) or until they prove themselves over a bigger sample (how about Jake Lamb, or if you want to go a little deeper, Preston Tucker or Carlos Frias). One such prospect that falls into the latter category is Roberto Osuna, who also happens to be the youngest player in the major leagues.

Osuna had a dominating spring and was often mentioned in the same breath as fellow prospect Miguel Castro, in part because of their age – both were barely 20 on Opening Day – and in part because of their identical 2.19 ERA in 12.1 March frames. Most had the pair ticketed for either High-A or Double-A because of their youth and lack of experience at advanced levels, but both broke camp as big leaguers. Castro caught our attention first because he earned saves but he was only okay before a recent demotion to Triple-A, registering a 4.38 ERA and striking out 12 batters in 12.1 innings. On the other hand, Osuna has been spectacular, pitching 19.1 innings and allowing only two runs while striking out more than a batter per inning.

The Blue Jays signed Osuna out of the Mexican League in 2011, where he was pitching as a 16-year-old. He played in short season leagues in 2012 before advancing to the Low-A in 2013, where he was the youngest player in the Midwest League. Osuna pitched much better than his 5.53 ERA suggests, striking out almost 11 batters per nine but required Tommy John surgery after only 42.1 innings. Upon returning late in 2014 Osuna made seven short starts in High-A and then pitched 12.1 innings across six appearances in the Arizona Fall League. At both stops, he again struggled with run prevention while striking out opponents in bunches. All of that history adds up to 141 innings of minor league experience, which combined with his age gives you an indication of how much of a long shot Osuna was to appear in the majors this year, much less find success.

Despite the unlikely profile, Osuna’s arsenal absolutely is major league caliber. His four seam fastball is shaped much like Aroldis Chapman’s and while it obviously doesn’t have triple digit velocity, the 96.04 mile per hour average is good for a top 20 mark among relievers. He complements the fastball with two above-average secondary pitches, against which batters have mustered all of one hit. Osuna’s nasty, tumbling changeup has long been considered his best secondary offering and while batters have whiffed at a high rate when they swing, they’re not swinging often enough because he isn’t finding the zone. Osuna’s slider is his clear third pitch but he seems to be gaining confidence in it as he throws it more frequently and with greater success. Unsurprisingly, he’s utilizing it as a put away pitch against righties, locating it down and away primarily when he’s ahead in the count.

Osuna’s fantasy value is tied to his role and while he’s purely a spec saves play for 2015, his future is uncertain. With Castro’s demotion to Triple-A, Brett Cecil has reclaimed ninth inning duties but his left-handedness and shaky start to the season likely have him on a short leash. Assuming Toronto wouldn’t pursue Rafael Soriano or another option via trade (which they may), Osuna is the most likely successor if Cecil falters. Alternately, Osuna’s future could be as a starter. Prior to 2015, he was being developed as a starting pitcher and he has the three pitch mix to be successful in that job if he can keep himself in shape. His command would probably deteriorate to some extent if he returns to that role, but he’d still have high strikeout upside.

Regardless of where Osuna ends up in 2016 and beyond, we should take note of and celebrate what he is accomplishing right now, even if it currently has marginal fantasy benefit. Since 2000, the only pitchers aged 21 or younger with a better FIP are Joba Chamberlain in 2007 (24 innings) and Shelby Miller in 2012 (13.2 innings). Will he be this good the rest of the way? Probably not. He gives up too many fly balls and eventually some of them will clear the fence, which is why his xFIP is more than a full run greater than his FIP. Nevertheless, what Osuna is doing as a 20-year-old just isn’t very common and when given the choice of what to watch, maybe Osuna’s next outing should earn the screen instead of the newest shiny toy’s debut.

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