Marlins-Tigers Trade: The Good News for Dontrelle Willis

In the wake of the Marlins-Tigers mega-deal, much of the discussion has focused on Dontrelle Willis' transition to the American League.

Because of his marketability, Willis has achieved a degree of fame far exceeding his actual value. His slipping performance in the last few years is evidenced by his numbers.

Consider Willis’ averaged lines from his first three years (2003-2005), followed by his stats from 2006 and 2007:

 

2003-2005

3.28 ERA, 8.6 H p/9IP, .67 HR p/9IP , 2.64 BB p/9IP, 6.83 K p/9IP, .29 HBP p/9IP

 

2006-2007

4.51 ERA, 9.9 H p/9IP, 1.06 HR p/9IP, 3.58 BB p/9IP, 6.43 K p/9IP, . 694 HBP p/9IP

 

Clearly, Willis is no longer the pitcher he was two years ago. His control, once an asset, is now well below average—particularly when taking into consideration his enormous HBP totals. His strikeout rate has dipped, and his home run rate has almost doubled.

Given these obvious shortcomings, Willis' impending move from the weak National League to what might be the toughest division in baseball seems like a recipe for disaster.

ESPN’s Keith Law discussed the subject in his blog:

“Dontrelle Willis, on the other hand, won't fare as well in the transition. Willis' stuff hasn't been that overpowering in about two years, and his fastball command was poor for the entire 2007 season. The same aspects of his delivery that give him so much deception also make his delivery hard to repeat and put more stress on his arm. As a result, he's not the same pitcher he was from 2003-05. He's thrown 200-plus innings for the past three years and may just be a guy who can soak up those innings at a below-average level, which has value but not something that matches his reputation. In the tougher league, he might just be a fifth starter.”

In fairness to Willis, though, Law ignores a key change the lefty will encounter in his new home—a change in the defense behind him.

The following are Willis’ lines from 2006 and 2007:

 

2006

3.87 ERA, 9.44 H p/9IP, .85 HR p/9IP, 3.35 BB p/9IP,  6.45 K p/9IP, .76 HBP p/9IP

 

2007

5.17 ERA, 10.6 H p/9IP, 1.27 HR p/9IP, 3.81 BB p/9IP, 6.40 K p/9IP, .61 HBP p/9IP

 

Other than ERA, two numbers stand out—the jump of .4 HR/9IP, and the increase of more than a hit for every nine innings.

The jump in HR is a concern—but given the stasis of the other numbers, it's likely to be an aberration. And even given the .4 HR jump, there's still a jump of .85 hits per nine that remains unaccounted for.

Enter the Marlins defense.

In 2007, Florida had the worst defense in Major League Baseball. According to Baseball Prospectus’ FRAA (Fielding Runs Above Average), Florida turned 41 FEWER runs into outs than the average MLB team.

In 2006, Florida’s defense had registered at slightly above-average—a +10. The massive drop of 51 potential outs would seem to go a long way toward explaining the increase in Willis’ hits allowed and ERA.

The Detroit defense, meanwhile, saved 24 more runs than the average MLB D in 2007. Though the Tigers will suffer in exchanging Brandon Inge’s Gold Glove defense for Miguel Cabrera’s waddling efforts at the hot corner, the arrival of Edgar Renteria and the substitution of Carlos Guillen for Sean Casey at first base should keep the team's defensive performance more or less steady.

If Willis' inflated HR numbers turn out to be a fluke and these defensive projections hold, it wouldn't be unreasonable to expect his 2008 ERA to fall back toward the 4.50 range.

With a few breaks, in fact, Willis would be an excellent addition to the Tigers' staff.