I always go back to what Kevin Goldstein (former BP writer, current Astros pro scouting coordinator) says about player comps – they’re generally a bad idea and can be much more disinformative than informative. However, a physical comp can be a good way for a baseball fan to get a better idea of visualizing a prospect that they likely have never seen play. I’ve heard a number of them that were both appropriate and helpful, like that Simon Castro is built like Jose Contreras and that Mike Trout is built like Brian Urlacher (still probably my favorite physical comp).

It’s very easy to throw around the Pedro comp to any undersized righty from the Dominican Republic who throws really hard, and among all pitching prospects out there today, Carlos Martinez gets it the most. At a quick glance, you can see why (he throws real hard and is from the DR). But, beyond the simplistic comp, let’s dive into the differences between the two, along with what we can hope to expect from Carlos Martinez as his career advances. But first, a fun fact. Carlos Martinez checks in at 6’0”, 165 pounds and is accurately described as having a slight frame, but if his frame is slight, what was Pedro’s? In his days as a prospect, Pedro was 5’11” and 135 pounds. 135 pounds! That’s 82% of Carlos Martinez! Anyway, moving on…

So instead of disinforming, let’s look at what Carlos Martinez is as a pitcher. Yes, he throws hard – he can sit in the high-90’s on a good day (Pedro did that too!). Yes, he’s got the potential for a major league quality out pitch in his curveball (Pedro had a dominant change-up, but let’s not let facts get in the way of this comp!). But it’s the improvement in his command and consistency that has allowed him to have success in his first taste of the upper minors this year – and that all starts with simplifying his mechanics and repeating his delivery. When Martinez gets on top of his fastball consistently, he can generate ground balls at a very high rate. In fact, in he has a career 52% GB rate, which is only overshadowed by his fantastic 57% GB rate in Double-A this year.

Unfortunately, it’s impossible to talk about his stuff without mentioning the inherent risks. You can’t go around assuming every short pitching prospect with some violence in his delivery will end up in the bullpen. On the other hand, guys like Johnny Cueto, Roy Oswalt and Gio Gonzalez are not the rule, but the exception. The fact is, Martinez is less likely to become a 200-inning starter than someone who’s 6’4”, 220 pounds, but in fantasy, it becomes a less relevant argument. Sure, he’s less valuable to the Cardinals if he doesn’t stick in the rotation, but if he’s a shut down closer (which is Plan B here), his fantasy value should remain high. And the odds of Martinez not becoming either a front-line starter or shut-down reliever should be around the same as any other pitching prospect, even though the split between the two outcomes is less ideal.

So what makes the Oswalts, Cuetos and Gios of the world successful where other shorter pitching prospects have failed? The crude answer is twofold. First of all, it’s physiological. Until biomechanical scouting becomes a thing instead of a pipe dream, it’s nearly impossible for us to predict which shoulders and elbows will be able to take the pounding of a starting pitcher’s workload. So instead, we look at the skill differentiator: the ability to keep the ball on the ground. Conventional baseball wisdom says that the reason shorter pitchers are less successful as a group is because they cannot generate the downward plane necessary to keep the ball on the ground. However, Oswalt (47.2% GB), Gonzalez (47.4% GB) and Cueto (44.8%) have been able to maintain ground ball rates above league-average. And as I mentioned earlier, Martinez (51.9% GB in minors) has these same tendencies.

Yesterday, Martinez had his most impressive Double-A start of his career in the playoffs for Springfield, going 7 shutout innings with 4 hits, 1 walk and 7 strikeouts. On top of that, of the 14 outs he did not record via the strikeout, 13 were on ground balls (including 1 DP). It’s hard not to get too excited about Martinez, and he’s not making it any easier. I put him at #27 on my mid-season dynasty league prospect rankings, and he will likely be higher on my 2013 list. After all, he’s just like Pedro**!

Carlos Martinez at age-20 in Double-A: 2.90 ERA, 1.18 WHIP, 2.64 K/BB and 7.3 K/9 in 71 1/3 IP.
Pedro Martinez at age-19 in Double-A: 1.76 ERA, 1.15 WHIP, 2.39 K/BB and 8.7 K/9 in 76 2/3 IP.

** Wait, what?