The Astros starting rotation already has one new young pitcher, Bud Norris. Previously, 25 year old Felipe Paulino spent a couple of months in the rotation. I think it's safe to assume that Yorman Bazardo will make a start at some point this season....perhas as early as Mike Hampton's scheduled turn, if Hampton's injury keeps him out. I wouldn't be surprised if Paulino or Polin Trinidad make a start or two after the September call ups.
This site will calculate major league equivalent (MLE) estmates for minor league player's stats. Let's see if the Astros' pitchers' MLE tells us anything interesting about what we can expect, or in the case of those who have pitched in the majors this year, whether the MLE was reasonably accurate. Don't expect anything definitive from this exercise, because most of the comparisons have significant sample size problems, either at the minor league or major league level. But maybe we add this to our bits of information on what to expect from the youngsters this season, and look back at the MLEs when the season is over to see if they provided anything useful. The MLEs are available as Fielding Independent Pitching stats (a version of ERA which is is independent of defensive luck).
FIP MLE (2008 AAA stats)
Felipe Paulino 4.95
Bud Norris 4.22
Yorman Bazardo 5.15
Polin Trinidad 7.43 (AAA/AA)
Paulino hasn't pitched many innings in AAA this year, and Norris hasn't pitched many innings in the majors yet. But we'll go ahead and compare their MLE to the ML FIP this year. Paulino's 2009 major league FIP is 5.49, and if that stat was limited to starts only, the FIP would fall by at least a half run. In other words, Paulino's MLE is fairly close to the actual ML result. Norris has only pitched 21 innings and has a 3.81 FIP so far in the majors. That is less than one half run off his MLE; and, frankly, I wouldn't be surprised at all if Norris' overall ML results move closer to the MLE of 4.22 as the season progresses.
Bazardo's MLE doesn't portend results nearly as good as Norris'. And, of course, this is because FIP frequently will appear to discount "pitch to contact" players with mediocre strike out numbers, whose ERA may look better than it really is, due to above average defense. Surprisingly, Mike Hampton's FIP on the season is 4.57, which indicates that he hasn't been pitching as badly as we might think. The fact that Bazardo's MLE is considerably higher than Hampton's FIP may mean that the Astros' attempts to keep Hampton in the rotation over Bazardo are not entirely illogical. At this point, though, if Hampton's injuries prevent him from pitching effectively, Bazardo may become a more logical choice. Right now, Bazardo would also appear to be a better starting rotation option than Trinidad, who may not be ready for the majors based on his MLE.
Just for comparison sake, let's look at two young pitchers who have succeeded in the bullpen, Alberto Arias and Jeff Fulchino. Because Arias only pitched 17 innings in AAA this year, I will compare his 2008 AAA MLE, which is a FIP of 3.86. His current 2009 ML FIP is a slightly lower 3.34. I think Arias' 2008 MLE may be somewhat inflated by 49 innings pitched at hitter friendly Colorado Springs. If you accept the updated ZIPS projection, Arias' current 3.34 FIP is just about where he will end up. Fulchino's 2008 MLE is a FIP of 4.03. Fulchino's actual FIP so far is 3.75, even though the ZIPS update projects a slightly higher 3.88 on the season. The fact that Arias and Fulchino were used as starters in AAA, but are used as relievers in the majors, also may account for a lower actual FIP, compared to the MLE.
Since we are discussing relief pitchers, what does Sammy Gervacio's MLE tell us to expect? His AAA MLE indicates a FIP of 4.30, which isn't too bad. Broken down by platoon splits, Gervacio's MLE versus RHB is a very good 3.81, but his MLE versus LHB is a not so good 5.79.
As indicated above, the MLE can tell us what kind of splits to expect from minor league pitchers. Felipe Paulino has a big problem with LHB, as evidenced by a 6.80 MLE against lefties (compared to a 3.45 MLE on righties). The MLE split correctly indicated Paulino would have problems with lefthanded batters in the majors, borne out by lefties' 1.216 OPS against in the majors. Perhaps Felipe needs to work on a new pitch to combat LHBs, or improve an existing pitch (maybe a change up) which might be effecttive against lefties. In fact, the key to Paulino making the necessary jump to consistent starting pitcher could well be finding a weapon to get LHBs out.
All in all, the current MLEs seem to have been reasonably good indicators of how young Astros' pitchers will perform.