A pretty common question we see in FanGraphs chats is what one statistic we’d use to evaluate pitchers, if we could use only one. The truthful answer is always a non-answer: You shouldn’t ever use just one statistic. It’s an unrealistic hypothetical, and good evaluation is done with a blend of different data. But I will say that I tend to look at xFIP early on, just to get a sense of what I’m dealing with. It’s a number that can scrape out a whole bunch of noise. Something I noticed is that, this season, Max Scherzer posted a 3.16 xFIP. Rick Porcello posted a 3.19 xFIP. Both were full-time starters for the same team, and one of them, presumably, is about to win the American League Cy Young Award.
It’s a comparison that’s interesting enough on its own, but adding more significance to the comparison is talk that the Tigers will explore trading one of these two pitchers in the weeks and months ahead. There’s skepticism everywhere that a team like the Tigers would actually think deeply about moving Scherzer, considering everything, but the ace is one year from free agency and he’s represented by Scott Boras. Porcello is two years from free agency, and the Tigers have Drew Smyly just about ready to resume starting. Really, the Tigers aren’t limited to picking one between Scherzer and Porcello, but things could well work out that way. And in talking about this, xFIP is only the start.
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