The hottest Astro in the month of July isn't Jose Altuve. Don't get me wrong. El Escorpion is still on fire. But, he doesn't hold a candle to what Chris Carter is doing right now.
In 14 games and 59 plate appearances, Carter is hitting .333/.373/.759 with six home runs and a stolen base. He's generated 0.8 fWAR in that span, which is basically his entire contribution WAR-wise this season (he's at 0.9 on the year).
What changed?
Well, Carter is hitting a ton more line drives this month than he usually does. His line drive rate spiked to 29 percent, up 14 percent over his June average and eight percent over his career average. He's also hitting 40 percent of his fly balls out of the park, which is unsustainable.
Does that mean his rise is a fluke? Will he turn back into Karter soon?
Well, we also have pitch data to see if he's made an adjustment on how he's approaching at-bats. Basically, the reason Carter has turned into one of the best hitters in the majors this July is he's hammering fastballs. He's been worth six runs above average on fastballs this month alone, despite being three runs under average in May and June combined.
The number of fastballs he's seeing hasn't changed dramatically, but his success on those fastballs has increased. Check out his slugging percentage on fastballs in July:
Now, compare that to his success through June:
The difference, it appears, is that Carter has been able to better hit those fastballs low and away. He's also become more adept at laying off those fastballs when they're off the plate. That puts pressure on pitchers to hit their spot in that lower outer quadrant. See that corner on his July slugging heat map? He's able to basically become a singles hitter on those pitches. Check out where Scott Kazmir put a changeup last night on Carter's two-run single up the middle:
Same spot, different pitch, but same result. Carter is able to drive the ball up the middle. Oh, and if pitchers don't hit that quadrant? Look out. Carter has hit four of his six home runs this month on balls that got too much of the plate while staying in that low quadrant or that came up too high while staying outside. As an example, here's his chart on home runs per balls in play for July on fastballs and changeups.
Opposing pitchers will figure this out. They'll stop throwing him balls down there and start working him up and in, where's he's got a significant hole. But, for now, it appears Carter will continue to make hay on fastballs low and outside.
Thanks to Brooks Baseball for the outstanding charts and to FanGraphs for the pitch value data.