Billy Butler’s Extension and Future Power

Underrated by casual baseball fans because he plays for the Royals, and overrated by many Royals fans because they don’t have many recent examples of what a good position player looks like, Billy Butler has agreed to a four-year, $30 million extension with Kansas City that also includes a $12.5 million club option for 2015 (the $1 million buyout is included in the $30 million guaranteed above). This is a good deal for the Royals, but given Butler’s age it is worth taking a look at how Butler might continue to develop as as hitter and provide the team with even more value.

Butler was arbitration eligible for the first time this off-season, so the the contract buys out all three of his arbitration seasons and his first year of free agency. Assuming a current average open market price of $5 million per marginal win, a conservative five percent annual increase in that price, and the usual 40/60/80 structure of Butler’s three arbitration wins, the guaranteed portion of the contract values him as about a 2.5 win player.

Projection systems understandably like Butler’s bat (wOBA figures are calculated using 2010’s linear weights). ZiPS projects Butler to hit .304/.372/.467 (.369 wOBA) in 2011, which in 2010’s run environment is worth 28 runs above average over 700 plate apperarances. CAIRO is slightly less enthusiastic, projecting .297/.366/.462 (.358 wOBA) for 21 runs above average. Taking the middle route, let’s call Butler a +25/700 hitter for 2011.

In the field, Butler isn’t going to erase any memories of Keith Hernandez, to say the least. Since taking over full-time at first base in 2009, Butler has been below average according to UZR, and UZR is more optimistic than DRS, which is more optimistic than the Fans Scouting Report. Calling him a -5 first baseman would put him right at the point of the adjustment for designated hitter (-17.5), which is Butler’s best “position” (and where he’ll probably end up when stud prospect Eric Hosmer is ready for the majors).

Adding it all up: +25 offense, -17.5 defense plus position, plus 25 American League-replacement level, adjusted down for playing time makes Butler around a three win player. Some might be consider that a bit low (although it doesn’t take into account Butler’s double play issues), but it’s probably in the ballpark. Since the Royals are paying him as if he isn’t quite that valuable, this is a “win” (if we must use that term) for the Royals in monetary terms alone. In addition, whlie Butler does get the security of guaranteed money, not only is he giving up any shot at free agency until he’s 29, if he performs well, the Royals will almost certainly pick up his club option, delaying his free agency until he is 30. This is a big win for the team, who can either keep a valuable hitter or buy him out if injury or a mysterious loss of bat speed strikes. This is a nice piece of work by Dayton Moore and his front office. I’m not sure I can say the same for Butler’s representation — I can see giving up one year of free agency or one club option, but both? Of course, fans understandably don’t care too much about that angle.

Butler will be only 25 next season, so he has still got some time to grow offensively. Thus the Royals have a good chance of getting even more for their money as (conservatively) projected above. Butler is an interesting case because while he is a poor defensive first baseman not known for his athleticism (although have already been some reports from fans that “he’s in the best shape of his life”), he doesn’t have the offensive profile one expects to accompany such a characterization. He relies heavily on contact and ground balls in play while so far displaying merely above-average power (For more information on Butler’s plate approach, complete with heat maps, check out Jeff Zimmerman’s work). Because of his “body type,” he looks like a player who should have power, and although he hit 21 home runs and had a .191 isolated power in 2009, his 2010 ISO dropped back down to .151. How much power might Butler develop in the coming years? Is he going to have a “breakout” (whatever that means) anytime soon?

Players generally are still adding power at Butler’s age, but we can try to be a bit more specific (and informal) and compare him a more specific population. Let’s employ an (admittedly crude but perhaps charmingly simple) approach. I took his most similar players through age 24 (Butler’s age in 2010) from his Baseball-Reference player page and averaging the change in their isolated power for each season from age 24 to 30 (and not including players for years they did not play, of course), I found that going into their age 25 and 26 seasons, they did not, on average, gain isolated power, and it actually went down a bit (ISO oversimplifies, as it might increase due to different rates of decline for batting average and power, but for the purposes of a blog posting, it works well enough).  I did, however, find sharp increases in the age 27 and 29 seasons, which would imply that Butler might not see his power spike for a couple of years. But whatever merits those similarity score-based comparisons might have, I’m not sure how well they really fit here. The majority of the hitters listed were left-handed, and about half of them were outfielders. That doesn’t sound like a perfect group of hitters to compare with the right-handed-hitting, lead-footed Butler.

Searching for more relevant comparisons, I took a look at Butler’s three most comparable players according to ZiPS (although Dan Szymborski, ZiPS’ creator, should not be blamed for what I do with this list): Paul Konerko, Sean Casey, and Mike Sweeney. All three were first baseman, Konerko moved off of third (like Butler did early on) and had a decent or good average and only decent power through Butler’s age. I’ve included graphs of their development by age for both overall offense (as measured by wOBA) and isolated power.

Don’t concern yourself with the specific numbers here, as those are effected by the particular run environment of the run, park, season,and league. The “contour” of the aging curve after age 24 is what we’re concerned with here. Neither Konerko nor Casey’s overall production took off at 25, and Casey (a curious comparison since he’s a left-handed hitter, whereas Butler is a righty) saw his power decline precipitously (other than one out-of-nowhere season) after that age. Konerko stayed about the same until he had a poor age 27 season, after which started to improve more noticeably in overall production and in terms of his power in particular. Sweeney’s power and wOBA did take off in his age 25 season, but there are at least two caveats here: first, Sweeney only became a full-time major leaguer at 25, so there are sample size issues for the previous seasons; second, Sweeney was still a full-time catcher in his age 24 seasons, and moved to first base and designated hitter for his first full season at 25, which might have made a difference as well. There are good reasons that Sweeney shows up as a comparison for Butler, but I think Konerko and Casey are probably better. They also fall in line with what we saw from Butler’s Similarity Score comparables — after 24, a power spike usually doesn’t happen until 27-29.

One shouldn’t make too much of these comparisons. There are many more that could be made using other methods. Ultimately, each player has his own personal “ageing curve” (although we only discover it in hindsight). But it’s sometimes more interesting to look at concrete cases than simply to hitter ageing “in general.” While Mike Sweeney stands out as a hitter who suddenly “got good” at 25 and didn’t really “develop” after that (other than getting hurt), for reasons stated above, Butler is probably closer to the career path of the others examined. Butler is already a good hitter, of course, but if he follows most of his comparable players as listed here, a big jump in his power and production may have to wait a few more years. Fortunately for the Royals and their fans, those years are now controlled by the team.