Is Mike Aviles Really a Major Downgrade at Short?

When the Boston Red Sox traded away their starting shortstop, Marco Scutaro, to free up payroll, a wide array of fans and pundits let out a collective moan across twitter and  many other media outlets. Here at Rant Sports, my esteemed colleague, Mark Hock, lamented the move and asked if the Red Sox were even trying to compete in 2012. While there are plenty of reasons to worry about the Red Sox, the drop off in production at shortstop might be the most overstated one.

Marco Scutaro was great forBoston last season. fWAR credits him with being worth 2.9 wins in 2011, thanks in large part to his .299/.358/.423 batting line giving him a .343 wOBA. He played solid, if average, defense at short, with UZR giving him 0.7 runs above average and FRS crediting him with 1 run saved above average. Among SS with over 300 plate appearances, Scutaro ranked sixteenth in baseball in total value and eight in hitting (by wRC+). That is excellent production from a shortstop and it is not easy to replace it.

However, last season was Scutaro’s second best season ever at the plate and ties for the second most valuable season in his career. His .423 slugging percentage was the highest of his career, as was his .299 batting average. At 36 years old, he is a bad bet to repeat his 2011 production, especially since much of his success can be attributed to his .312 batting average on balls in play, which is nearly .20 higher than his career average. Looking at some projections for both Scutaro and his primary replacement, Mike Aviles, the differences don’t seem too dramatic.

Bill James projections actually have the two shortstops producing identical results at the plate with Scutaro putting up a .318 wOBA and Aviles producing a .319. James sees them accomplishing that production in very different ways, with Aviles struggling to get on base, but hitting for a respectable amount of power and Scutaro continuing his patient approach but rarely ranking up extra base hits. Zips projections has a slightly larger gap between the two, thanks to a less bullish view of Aviles’ power. Even Zips, however, has the difference between the two at just around a 5% advantage for Scutaro.

On the other side of the ball, the issue becomes much more difficult to decipher. Scutaro represents something of a black hole for defensive metrics. He is probably around an average fielding shortstop, which is where UZR rates him. However, Total Zone likes his glove a lot, while Fielding Runs Saved is quite negative. Regardless, he is not an elite fielder, nor is he a liability at the position.

Mike Aviles’ reputation is that he can barely stick at shortstop. Much of this seems to be driven by the fact that he was moved off the position in 2009, when he was a member of the Kansas City Royals. At that point, Aviles was struggling in every way in his second year as a major league player, especially at the plate. However, the fact that Aviles was replaced by Yuniskey Betancourt- the worst fielding shortstop in all of baseball- actually tells us more about Royals’ GM Dayton Moore’s inability to recognize good fielders than it does about Aviles. Aviles has positive numbers in every defensive metric as a shortstop. His poor defensive numbers all come from other positions, where he has played fewer innings. It may be that the advanced metrics do not accurately access his true talent, but even if they are heavily regressed, there is no statistical evidence to suggest that he is a worse defender than Scutaro; there is evidence suggesting he is better.

Certainly, Marco Scutaro is the better player. He walks nearly twice as often as Aviles and strikes out less. In the field, he more of a known quantity, but he has no real advantage over Aviles. However, the difference between these two players is easy to exaggerate. While Scutaro has the superior approach and has been better at the plate recently, he is also a hitter with virtually no power who has rarely ever produced even average results on balls in play. Mike Aviles doesn’t have the same eye, but he has made up for it by hitting the ball harder, producing more power and a better result when he puts the ball in play. He is moving to a slightly more favorable environment for these skills as well. Given the minor differences in their projections, it is unrealistic to say that Aviles is any major downgrade from Scutaro. In terms of wins, starting Aviles in place of Scutaro is almost a lateral move, costing the Red Sox no more than .5 a win by any reasonable projection.