When Kevin Towers pulled the trigger to acquire Chris Johnson last week, there was a lot of head-scratching, a common response to Kevin Towers moves. Who? some asked. What value does he add? others muttered.
We all know how it's gone since then: Johnson has hit a slash of .324/.361/.794 with 5 home runs and 15 RBIs since being acquired by the team. If WAR is your more your style, then he's racked up nearly a win above replacement since joining the team, and that's even taking to account that he has a concrete glove.
The intent here isn't to rub the move in everyone's noses (though it should be pointed out again that Kevin Towers just might have experience and just might know what he's doing, sometimes), or even to try highlight Johnson's play. We all know he's been great so far. Instead I want to look at whether its sustainable, and how the lineup now looks with him in it.
The first concern we should have is "Just How Sustainable Is This?" I hesitate to write this, because the last time I questioned the possibility of a player sustaining a hot start they immediately suffered an injury and haven't been the same since. Also, it should be obvious that a wOBA, or weighted On Base Average (in other words, a ratio of how many bases a player averages, if each base is "weighted" to reflect its increasing value), of .479 is not going to continue.
We might not need to fear the cliff, however. One of the first things people look at to see if a player is just getting lucky in a steak is the BABIP, which is the batting average relevant to the balls put in play. A player with an abnormally high BABIP suggests that they're putting a lot of balls into play that are somehow dropping for hits, when some normally would be fielded successfully. It's not sustainable, in other words. Likewise, a player with an abnormally low BABIP might be extremely unlucky, in that too many ball are being fielded successfully.
So Chris Johnson has an abnormally high BABIP since joining the team, right? Wrong! His BABIP is .279, which is well below his average. He's generating video game numbers, but not because he just happens to be hitting a bunch 'where they ain't.' A large part of this is because the times he is getting a hit, it's for a high value (extra bases or home run). 55% of his hits since becoming a D-back have been extra base hits (XBH), whereas his career average is 8.7% (and the MLB average is 7.7%). So obviously that's going to go way down.
Another piece that might be making it easier for Johnson (and that will change as pitchers change their approach) is the pitch selection he's seen. He hasn't seen more fastballs, but the ones he has seen have been slightly slower by almost 2 mph. He's also getting fewer sliders. Pitches with tricky movement are difficult for young players, and it also separates the great from the merely good. He might be doing well not just because of some unknown hot streak, but also because the pitches he's seeing are easier to handle. If true, it's not difficult to imagine opposing pitchers will begin to adjust.
So he probably should adjust back downwards. Where then, does that leave the D-backs? Luckily, there are a few guys in the lineup putting up very good numbers so far. The following players all have more than 3 fWAR so far this season: Aaron Hill, Miguel Montero, and Paul Goldschmidt. Jason Kubel should get past 3, and Justin Upton could make if he finishes the season strong. Meanwhile, Chris Johnson has already accumulated as many HR and fWAR as the man he replaced. Add in a solid backup in Willie Bloomquist, and the D-backs have a solid looking lineup.