Rodríguez vs. the A’s: what to watch for

After a few days off, it’s hard to predict just how players will perform. Pitchers could be well-rested and able to tap into that muscle memory easily, hitters might not have lost their timing, but the opposite can just as likely be true. Of course, these are professional athletes, so we should at least start with the assumption that they’ll all be starting from a place of competency.

As great as Dereck Rodríguez has been in his limited time with the Giants this season (46.2 innings), he’ll be facing an A’s team that’s won 20 of the last 26, which includes 3 out of 4 wins against the Astros in Houston. He has five pitches — fastball, sinker, slider, changeup, and curveball — but which will be most effective tonight?

Per FanGraphs, Jed Lowrie, Mark Canha, and Khris Davis are the top three fastball hitters in the A’s lineup. Stephen Piscotty and the Matts (Joyce, Chapman, and Olson) are all good, too, but it’s these top three who do the most damage, producing 29.5 runs above average combined (remember, all advanced stats calculate success in runs and about every 10 runs equals one “win”).

Rodríguez throws his 93 mph fastball (on average) approximately 33% of the time. There’s a chance he’ll throw it a bit less tonight, if only because of the lineup he’s facing. He’s averaging 92 mph with that sinker, though, with nice running movement in on right-handed hitters (away from left-handed hitters). This is good because those top three hitters for the A’s haven’t done as well on pitches that run away from them. They’ve combined for a -1 run below average on sinkers.

They’ve also had trouble with the curve (-3.2 runs below average) and the slider (-0.9 runs), the latter pitch one that Rodríguez throws only 11.38% of the time. He throws his last pitch, the changeup, more often than the slider (15%), but it’s a pitch that top three for the A’s can really hurt (10.4 runs above average).

We see how the time that major league pitchers won’t change their approaches because their approaches are what put them in positions to succeed. They have confidence in their stuff and believe that if they execute their pitches properly, they can’t be hit. And that makes sense — the pitcher always has the advantage. He and the catcher are the only two people who know what’s going to be thrown at any time.

Still, maybe Rodríguez should layoff the four-seamer a little bit tonight, if only against those three key hitters. It’s all about command, of course, and if he doesn’t have a feel for his other pitches or can’t hit the zone at all, then it’s going to be a long night regardless; but when his primary arsenal seemingly plays into the A’s hands, it’ll be interesting to see if he uses the knowledge going in or adapts on the fly.