Willingham and Bay by Dave Cameron January 29, 2010 Perception is a funny thing. After Buster Olney reported that the Nationals were willing to trade Josh Willingham again, I had a conversation with a couple of people about how well he would fit in with the Mariners. They’re not particularly new-school types, but I respect their opinions and wanted to know what they thought of him. Both thought he was okay, a decent role player who could inject some power but shouldn’t be thought of as an everyday player. One comment in particular stuck out to me, though – “If you think he’s a substitute for Jason Bay, think again. He’s not at that level.” Curiosity piqued, I decided to look and see just how large the gap is between Willingham and Bay. And, to my surprise, I learned that the answer is “not much.” They were born five months apart, Bay at the end of ’78, Willingham at the beginning of ’79. Bay made the majors as a 24-year-old, Willingham as a 25-year-old. They both share the same skillset: power hitting outfielders who draw walks and produce enough runs at the plate to compensate for below average defense. But even beyond the generalizations, they’re similar. Look at their respective wOBAs plotted on the graph below. In 2004 and 2005, Willingham racked up less than 30 plate appearances, so even though he’s got a dot on the chart, the performances aren’t meaningful. He wasn’t really a major league player until 2006, so focus on the years since. Since 2006, they have been very similar hitters. A weighted average of Bay’s wOBA since then is .377, while Willingham’s is .367. 10 points of wOBA over a full season is approximately 5 runs of offense. This is not a small sample. We’re talking about a couple thousand plate appearances, and the difference in offensive production between the two can only be categorized as minor. Yet, there is the perception of a huge gap between the two. Bay is a middle of the order slugger, while Willingham is a nifty role player who can mash lefties. That’s the narrative, and four years of facts hasn’t been able to change it. In reality, the difference between them is measured in fractions of a win. Bay is the better player – he’s outhit Willingham in three of the last four years, and his most recent performance came in the AL East, while Willingham has collected all of his performances in the NL. There are enough gaps to distinguish between them and say Bay > Willingham. But it’s a very small gap. And here’s the funny thing – you guys don’t even really disagree with this very much. The Fan Projections here on the site have Bay as a +3.1 win player for 2010, while Willingham is projected as a +2.9 win player. Even if we won’t admit it, we think that they’re basically the same player going forward, just giving a slight edge to Bay. So, with all due respect to my old school friend, I have to disagree. Josh Willingham is a substitute for Jason Bay. They’re practically the same player.