Yesterday, the Royals reportedly agreed to a two year, $12 million contract with free agent left-hander Travis Wood, helping round out a pitching staff that needed some additional depth due to the tragic loss of Yordano Ventura. Wood had several other suitors, and in order to help convince him to come to Kansas City, it appears that the team has offered him a chance to compete for a spot in the starting rotation.
There’s nothing wrong with giving him a shot in spring training, especially since Nate Karns — the likely fifth starter before Wood signed — isn’t exactly a surefire starter himself. But while Wood is a useful pitcher who could likely be a significant asset for the Royals in a bullpen role, the Royals should probably hope that he bombs his rotation audition and accepts a role in relief instead.
Let’s just start off with a table. Over the last three years, 51 left-handed starting pitchers have faced 500 or more right-handed hitters; here are the bottom five in terms of wOBA allowed.
Danks is in camp with the Braves on a minor league deal after the White Sox cut him last year. Corbin got booted from the Diamondbacks rotation last year due to his struggles. Rusin, likewise, was bad again as a starter, only to pitch much better after getting moved to relief work. Morgan was allowed to throw 113 low-quality innings because the Phillies weren’t trying to win. These are the southpaws that Wood has been keeping company with when asked to get right-handers out as a starting pitcher.
And the numbers don’t get much more encouraging if we remove BABIP from the equation either; Wood ranks 44th out of those 51 lefties in FIP vs RHBs, and 43rd in xFIP. When it comes to getting opposite handed hitters out, Wood has just performed about as poorly as any left-handed starting pitcher in recent years.
And that shouldn’t be a huge surprise, really, given his repertoire. He’s primarily a fastball/cutter/slider pitcher, and as a shorter guy without a lot of velocity, there really isn’t anything here that right-handers need to be afraid of. Most left-handed starting pitchers go after RHBs with a change-up that fades away from the barrel of their bat, or lacking that, a curveball or splitter that get a lot of vertical movement. Pitches that dive in towards a hitter’s barrel are generally the ones that do the worst against opposite-handed hitters, and Wood’s three primary pitches all do just that to right-handed hitters.
And while you can hide a right-handed pitcher with a platoon problem, because most teams just don’t have enough left-handed hitters to stack their line-up in an extreme way, left-handed starting pitchers see an incredibly high number of right-handed hitters. Let’s do another table.
In this table, we’re looking at the starting pitchers who had the platoon advantage the least often last year.
Hey, look, five lefties. And not coincidentally, basically every starting pitcher who held the platoon advantage less than 30% of the time was a left-hander. The range of platoon percentage among left-handed starters goes from Sale’s 15% to Scott Kazmir’s 27%, with the average in the low-20s. In other words, about 80% of the batters that left-handed starting pitchers will face in a season are right-handed.
Last year, pitching exclusively in relief, only 52% of the batters Wood faced were right-handed, which is why he allowed just a .285 wOBA despite a massive platoon split. Wood’s pitches work very well against left-handed hitters, and the Cubs maximized the number of lefties he could face without turning him into a pure specialist. But as a starter, that simply isn’t possible, and Wood’s job would then to be roll through heavily right-handed line-ups.
It’s possible, of course, that he could make some adjustments to his repertoire in order to reflect the return to the rotation. He used to throw a change-up, in fact, and the Royals could encourage him to bring that pitch back. Perhaps hanging out with Jason Vargas — another short left-handed starter, but one who has an excellent change-up — could help Wood become something he hasn’t been in the past. Realistically, if Wood was able to learn a quality change-up, he probably could be a pretty good solid starting pitcher, given his dominance of left-handed batters.
But more realistically, if Wood had confidence in his change-up improving enough to offset his big weakness, he probably wouldn’t have scrapped it. We can dream on anyone adding a new skill, but those types of transformations are more the exception than the rule. Most likely, Wood will continue to be excellent against left-handed batters and not so good against right-handed batters.
And if he’s put into the rotation, he’s going to see seven or eight right-handed batters in every line-up. There’s just no real reason to start anyone other than a premium left-handed batter against a guy like Wood, so every five days, he’ll be asked to get out a bunch of right-handers surrounding a guy like Joey Votto or Freddie Freeman. Without a significant adjustment in his repertoire, that’s a recipe for failure.
Wood doesn’t need to be a LOOGY, but asking him to face 80% right-handed hitters is fairly cruel, and not a great way to extract value from what he’s good at. Putting him in the bullpen, where he can go after good left-handed hitters, is probably the best way for Wood to succeed. Having him tandem-start with Karns could be particularly interesting, since they are fairly opposite types of pitchers, and could give teams wildly different looks for 3-4 innings each. But even as just a standard left-handed middle reliever, Wood can help the Royals bullpen, which needed some additional depth.
Barring a new mastery of a change-up that’s eluded him thus far, however, I wouldn’t advise counting on him as a rotation option. Getting right-handed hitters out is a requirement for left-handed starting pitchers, and thus far in his career, that’s not a skill Wood has shown he has.
Dave is the Managing Editor of FanGraphs.