Magic Wandy

For years now, the Houston Astros rotation has seemingly consisted of ace right-hander Roy Oswalt and a bushel of reclamation projects. Sure, Andy Pettitte and Roger Clemens passed through the neighborhood, but their presence was short-lived. For the most part, Houston has filled out spots two through five with forgettable names such as Brian Moehler, Chris Sampson, Brandon Backe, Woody Williams and Shawn Chacon. I mean, the club gave four starts to Runelvys Hernandez (nearly a win below average in only 19.1 innings), for goodness sakes. Oswalt (3.80 Fielding Independent ERA in 2008) is still going strong, but believe it or not, he was probably Houston’s second-best starter this past season. Lefty Wandy Rodriguez took a major step forward in 2008, pitching brilliantly in between two DL stints for groin and oblique injuries.

A few years back, Rodriguez looked like another Astros pitcher who could be thrown into the pile labeled “not Roy Oswalt.” Signed out of the Dominican Republic in 1999, Rodriguez compiled solid minor league numbers (3.72 ERA, 7.21 K/9, 3.07 BB/9), but his high-80’s heat and big-breaking curve were often launched into orbit during his first few seasons in the big leagues. Rodriguez posted a -2.25 WPA/LI in 2005 and “improved” to -2.00 in 2006. He struck out about six batters and walked near four per nine innings, uninspiring peripherals that led to a FIP ERA in the neighborhood of five. Wandy seemed to establish himself as a guy who would be about a half run better than a replacement-level starter, and at 28, he didn’t figure to improve all that much in the coming years.

However, instead of posting Moehler-ish numbers again in 2007, Rodriguez improved across the board. His strikeout rate jumped to 7.78 per nine innings, and he issued 3.05 BB/9, a slight drop from his minor league walk rate. In addition to sharpening his controllable skills, Rodriguez fared a little better in the capricious departments of the stat sheet. His BABIP dropped from an unlucky .325 in 2006 to .305 in ’07, and his 10.1 HR/FB% was much lower than his 11.9% mark in 2006 and whopping 14.8% figure in 2005. Wandy’s K/BB rate jumped from 1.56 in ’06 to 2.55 in ’07, and his FIP ERA lowered to 4.18.

Rodriguez did deal with a couple of medical issues in 2008, but when he took the mound, he was nothing short of excellent. His K rate climbed yet again, all the way up to 8.58 per nine innings. Wandy also showed slightly better control, with 2.88 BB/9. His FIP ERA was cut to 3.62, besting Oswalt. To give you an idea of where Rodriguez placed among his fellow starters, here are his ranks in several important categories (minimum 130 IP):

K/9: 13th
K/BB: 24th
FIP ERA: 24th

In the 25 starts that he made, Rodriguez pitched like one of the best 30 starters in the game. In other words, he pitched like an ace.

So, how has Rodriguez gone from back-of-the-rotation fodder to one of the more productive starters in the NL? The answer appears to lie in his curveball, a mid-70’s breaker with a ton of movement. Rodriguez has increased his usage of the curve from 21.4% of his total pitches in 2006 to 29.9% in 2008, and for good reason. By looking at Wandy’s pitch F/X data from Josh Kalk’s blog, we see that his curve has a dastardly combination of horizontal movement (5.65 inches) and vertical drop (7.41 inches). The pitch essentially drops in the zone as much as a 12-to-6 curveball, while also breaking away from a lefty (in to a righty) more than most sliders do.

By looking at Rodriguez’s pitch data from Stat Corner, it also becomes apparent that hitters are finding Wandy’s pitches more difficult to handle. Each year in the big leagues, Rodriguez has lowered his percentage of balls thrown and increased his percentage of swinging strikes:

2005: 38.4 Ball%, 7 Swinging Strike%
2006: 37.7 Ball%, 7.7 Swinging Strike%
2007: 37.2 Ball%, 8.1 Swinging Strike%
2008: 35.5 Ball%, 8.7 Swinging Strike%

Rodriguez’s Contact% has also decreased each year, from 83.4% in 2005 down to 79.9% in 2008. If there’s a negative to point out here, it’s that Wandy has increasingly become more of a flyball-oriented hurler, not always the best idea in a park where right-handers hit some cheap home runs (according to the 2009 Bill James Handbook, Minute Maid Park increased righty home runs by 15% between 2006-2008).

Will Rodriguez continue to post such impressive numbers in the future? Marcel has Rodriguez retaining most of the gains that he has made over the past two seasons, forecasting a 4.08 FIP ERA with 7.83 K/9 and 3.27 BB/9. Given his increased usage of his plus curveball, more swings and misses from batters and fewer free passes being issued, Wandy could be a magical selection once the top-tier pitchers have been snatched up.