Something is wrong with Shelby Miller

Arizona starter Shelby Miller trudges off the AT&T Park mound after facing four batters without recording an out in Thursday's third inning. Thearon W. Henderson/Getty Images

Sometimes baseball makes no sense.

The Arizona Diamondbacks are without center fielder A.J. Pollock, one of the 10 best players in the National League last season. Zack Greinke has a 5.25 ERA and just one win in four starts. Paul Goldschmidt is hitting .237. Shelby Miller -- THE TRADE!!! -- has been awful and made his fourth consecutive poor start Thursday, walking five in two innings on his way to a second straight early exit. Of course, the Diamondbacks beat the Giants anyway, 6-2, as Tyler Wagner pitched five scoreless innings in relief to complete their first four-game sweep at AT&T Park.

In other words: They're now 9-8 even though Greinke and Miller, their big offseason acquisitions, have combined for just two quality starts out of eight. Like I said: Baseball.

Anyway, the bad news was Miller's performance. In his previous start, he left after 1 2/3 innings after scraping his knuckles on the pitching mound. His mechanics again appeared completely out of whack Thursday, although he denied hitting his hand on the mound.

But you can see how his follow-through is more off-balance than last season, as he appears to be falling off to his left, with his right arm thus being dragged through and closer to the mound:

I saw Miller near the end of spring training and he didn't have any issues then, so this is something that popped up once the regular season started. He's allowed 14 runs and walked 11 batters while serving up five home runs in 14 2/3 innings, so this might involve more than just looking at video. As you would expect given the walks, his rate of strikes has plummeted. Last season, he threw his fastball in the strike zone 55 percent of the time; that's down to 46.7 percent. Since Miller throws his fastball so often -- he ranked sixth among starters in percentage of fastballs thrown last season -- he has to command that and get that good sink that leads to a lot of ground balls.

Anyway, assuming there's no injury here (his fastball velocity is down from 94.0 mph to 92.8, but if the mechanics are way off, that could make sense), this looks pretty easy to fix, or at least pretty easy to identify.

The Diamondbacks have overcome some of these early issues so far. Jake Lamb might be on his way to a breakout season, as ESPN Insider Eno Sarris just wrote about. Yasmany Tomas looks much improved at the plate, with a less hacktastic approach (he hit a long home run to deep left-center in this game off Johnny Cueto). Jean Segura is red hot. Patrick Corbin and Robbie Ray have looked good.

But this team needs Miller to perform. Because there was this trade ...