Big Z’s Loss of K’s

When Carlos Zambrano broke into the major leagues in 2001, he was the epitome of power pitching. The burly 6-5, 255 pounder pumped mid-90’s gas, and though he didn’t always know where it was headed, he racked up big strikeout totals. Zambrano punched out over 7 batters per nine innings between 2002 and 2003, before graduating into 8 K/9 territory. He whiffed 8.07 per nine in 2004 and 8.14/9 in 2006, before culminating at 8.83 K/9 in 2006.

However, as Big Z was racking up the K’s, his control was suffering. After walking about three-and-a-half batters per nine innings in ’04 and ’05, his BB/9 rocketed to 4.84 in 2006. Despite the higher strikeout rates, Zambrano’s controllable skills were headed in the wrong direction:

Zambrano’s Fielding Independent ERA’s, 2003-2006:

2003: 3.47
2004: 3.57
2005: 3.70
2006: 4.14

In 2007, Zambrano’s control took a (relative) step in the right direction, as he cut his walk rate to 4.20 batters per nine innings. However, that improvement seemed to come with a cost, as Zambrano’s K rate fell to 7.36/9. That shift produced further slippage in his FIP, as Big Z posted a career-high 4.58 mark.

Zambrano’s halted his rapidly ascending FIP in 2008, posting a 4.23 figure. He showed further improvement with the free passes (his 3.43 BB/9 was the lowest mark of his career), but Zambrano’s refined control came at the further expense of his strikeout rate. Big Z struck out a downright pedestrian 6.2 batters per nine innings, a far cry from his work just a few seasons prior.

While some might still categorize Zambrano as a power arm, he doesn’t really seem to fit the description anymore. Big Z once lit up the radar guns, but his fastball velocity has dipped in each of the past four seasons:

Zambrano’s fastball velocity, 2005-2008:

2005: 92.8 MPH
2006: 92.2 MPH
2007: 91.6 MPH
2008: 91.3 MPH

The 2008 version of Zambrano was at least more economical with his pitches. He posted his lowest pitches per plate appearance (3.80) and pitches/IP (16.0) since 2003. Big Z has also become more adept at getting batters to chase his offerings outside of the strike zone. His O-Swing% during his high-K 2006 season was 19.8%, but that figure climbed to 25.3% in 2007 and 25.7% this past season. With more pitches being thrown around the strike zone, batters seem less apt to lay off in hopes of coaxing a walk.

The combination of decreased velocity, K’s and walks leads one to believe that Zambrano is making an effort to show better control and put the ball around the plate more often. However, that improved command has significantly cut into his number of swings and misses generated. Once one of the more difficult starting pitchers to make contact with, Zambrano now ranks in the middle of the pack:

Zambrano’s Contact%, 2005-2008

2005: 77.9%
2006: 78.1%
2007: 78.8%
2008: 82.5%

It’s difficult to be very enthusiastic about the new, lower-octane Zambrano. Sure, his control is better. But he’s not going to be confused with Curt Schilling or Mike Mussina any time soon, and his whiff rate has dipped to the point where he’s actually below the NL league average of 6.99 in that department.

A pitcher can certainly be successful with a moderate K rate and worm-burning skills, but typically that sort of profile also requires the ability to paint the corners. Zambrano has improved in that regard, but his gains in the walk department still leave his control rating as just ordinary. When you combine a league-average K rate with a league-average walk rate, you get…a league average pitcher.

Still just 27, Zambrano has already accumulated nearly 1,400 innings on his right arm. That’s a Herculean workload, one that appears to be taken some bite off of his pitches. Courtesy of Baseball-Reference, we find that Zambrano’s most comparable player through age 27 is Ramon Martinez.

Like Zambrano, Martinez routinely crossed the 200-inning mark in his early 20’s, compiling plenty of strikeouts and walks along the way. However, such a massive workload at such a young age cut Martinez’s career short. Martinez’s major league career was effectively over by the age of 30 when his shoulder gave out, though he trudged on a little longer before calling it quits at 33. Perhaps Big Z finds his fastball zip this offseason, but all signs point to his days as a certifiable ace being over. As Martinez can attest, few youthful pitchers overcome such arduous innings totals to enjoy a lengthy career.