Over the course of the year, it's become clear that the Jays have a lot of good young pitchers. There's the fabulous major league quartet of Ricky Romero, Shaun Marcum, Brandon Morrow and Brett Cecil. There are the fringe guys - Jesse Litsch, Brad Mills, Marc Rzepczynski - who would not be fringe guys in many other organizations. There are a couple of big-name prospects who came over in trades - Kyle Drabek and Zach Stewart. There's the haul from the 2010 draft - Aaron Sanchez, Deck McGuire, Asher Woj, Noah Syndergaard. Not to mention guys like Henderson Alvarez, Chad Jenkins, and hey, throw Dustin McGowan in there.

You know who had a better season than any of those guys?

That would be Mr. Joel Carreno. The young Dominican has always sported shiny ratios, but has never made more than 16 starts in a season. This year he made 25, pitching 138 innings, and he busted out in a big way.

The first things that jump out upon inspecting Carreno's season stats are his strikeouts and walks. 173 strikeouts. 30 walks. Once again: 137.2 innings. That leads to ratios of 11.3 K/9 and 2.0 BB/9, both stunning numbers. They translate to a K/BB of 5.77, which would rank 9th best in the entire minor leagues for pitchers with 100+ innings. Carreno's home run rate is also excellent: he allowed eight all year, or 0.5/9 IP.

Despite these incredible peripherals, Carreno's ERA this year was a somewhat pedestrian 3.73. What gives? Well, the other important rate at this layer is the rate at which a pitcher allows hits. Carreno allowed 147 in his 138 innings. Not a terrible rate, but not great. Certainly not in line with how well he controlled the other facets of his game. So when I saw this I was a little mystified. It just struck me as wrong, somehow. How could a pitcher with such stunning peripheral stats allow hits at such a rate?

As it turns out, Carreno deserved to allow many fewer hits than he did. Further inspection reveals that Joel's BABIP against on the year was .392. That is awfully high. So high, in fact, that were he in the major leagues, he would have allowed the highest BABIP in baseball. By forty-four points. His BABIP was way higher than the major league "leader", Brandon Morrow, at .348.

This explains why Carreno's FIP, which as you may know is a stat that predicts a pitcher's ERA based on the things he is in complete control of - strikeouts, walks and home runs - was a spectacular 2.46 on the season. His xFIP, which normalizes a pitcher's home run rate to the standard 10.6%, was a slightly worse 2.72 (Carreno was a little lucky on home runs this year).

I'd imagine this is common in the minor leagues. Minor league fielders aren't nearly as good as their major league counterparts, leading to some absurdly high BABIPs. It's important to take this sort of thing into account when assessing minor league pitchers.

But wait, it gets better. Though most pitchers tend to allow about 30% of their balls in play to become hits (or, put another way, a .300 BABIP), some can expect to maintain a lower rate based on the types of hits they allow. Specifically, pitchers who don't give up a lot of line drives generally have lower BABIPs. And Carreno fits right in with that group.

Joel's LD% allowed this year was 14.4%, a very good number. For comparison, that would rank 4th in the major leagues - tied with Mat Latos, and behind Tim Hudson, Fausto Carmona and Jeremy Guthrie. The BABIPs allowed by those guys were .255, .249, .293, and .266, respectively. In fact, Carreno has always allowed a low LD% - his career mark stands at an incredible 12.8%. It's absolutely bizarre that a guy with such a low line drive rate could have allowed such a ridiculously high BABIP. Dunedin must have been putting some serious butchers on the field.

So while Carreno's xFIP of 2.72 is fantastic, I think it actually underrates his season because it doesn't take into account the fact that his BABIP can be expected to be lower than most based on his line drive rate.

Now, there are some caveats here. Joel is 23 and pitching in high-A. Second, I wonder if it's more common for minor league pitchers to maintain low line drive rates given a weaker level of hitters.

So while nobody is mistaking Joel Carreno for the best pitching prospect in the Jays organization (sorry, maybe the title is a little misleading), he certainly had a fantastic season. I can't speak for the rest of the minor league crew, but don't be surprised to see him climbing the prospect rankings this off-season.