Things have not gone well for Justin Upton this season. After posting an MVP-caliber season in 2011, Upton has struggled to reach the same level this year. The situation worsened on Tuesday, when Arizona Diamondbacks’ Managing General Partner Ken Kendrick criticized Upton’s performance so far this season. Later that night, Upton left out of the Diamondbacks’ starting lineup. Upton told reporters he was not pleased about the situation. And while that should have been the end of it, Upton found himself on the bench again last night. At this point, it seems like the only thing Upton can do to repair the situation is to start producing like his old self.
One thing that both sides agree on is that Upton’s performance has not been up to his usual standards. After hitting .289/.369/.529 last season, Upton’s slash line has dropped to just .243/.340/.365. Some of Upton’s struggles can be attributed to a thumb injury suffered earlier in the year. While Upton managed to avoid the disabled list, the 24-year-old outfielder missed a few games and had fluid drained from his thumb. Thumb injuries can often linger — and make it difficult to swing a bat — so it wouldn’t be surprising if Upton’s early struggles were a result of the injury.
Upton was so successful last season because he employed a slightly more aggressive approach at the plate. All of Upton’s swing rates (O-Swing, Z-Swing and Swing) jumped by at least 5% in 2011. This approach caused Upton to trade some patience for fewer strikeouts. And since high strikeout rates have always plagued Upton, it was encouraging to see him drop his K% to 18.7%.
But this season, he seems to have lost those gains. Upton has gone back to being incredibly patient. All of his swing rates have reverted back to pre-2011 levels. As a result, his strikeout rate has jumped to 22.6 — a number in line with his 23.8 career mark. Upton has made slightly less contact on balls thrown in the strike zone this season, but he’s making more contact on balls out of the zone. Upton could be swinging at worse offerings this year, and that could explain why he thinks he isn’t “squaring-up” the ball as much.
But that might not necessarily the case, either. Upton’s line-drive rate sits at 26.1, one of the highest performances in the league this year. He’s hit the ball fairly hard, but his batting average still sits at just .242. When things like this happen, it’s pretty easy to blame the luck dragons. Upton’s .298 BABIP would be solid for most players, but Upton’s career BABIP is .334. So, he should see some improvement as the season progresses. He’s also managed to cut his infield popups down to just 6.8% this year, and that should also help him raise his average.
There’s still the issue of Upton’s poor slugging percentage. His flyball rate is down this season — from 44.8 to 32.8 — and his HR/FB has also fallen to just 11.8%. That’s the worst Upton has performed in either category since his rookie season.
The easy explanation here is that the thumb injury either lingered for quite some time, or it continues to linger. Perhaps Kirk Gibson is trying to give Upton time to heal, and this isn’t a benching. But if that’s the case, Upton doesn’t seem to be aware of the plan. But if Upton’s thumb is still bothering him, it might be the reason why he’s been so reluctant to swing at pitches this year. And though he’s made good contact, he hasn’t been able to display his power much. Upton seems to have compensated for the injury by reverting back to his pre-2011 plate approach. As long as his thumb can handle it, Upton needs to start being more aggressive at the plate if he wants to return to form.