John Danks explains his September rebound

While John Danks couldn't quite return to his pre-surgery form in 2014, he did manage to finish the season in fine form. The White Sox's most veteran starter took a beating for most of July and August, but he reasserted himself in September. That doesn't show up in his monthly ERA (3.94) as much as it does in his .649 OPS allowed, which was 230 points lower than the previous two months.

Late in that month, we identified one potential reason for his improved effectiveness: a truncated windup that eliminates almost all extraneous motion. He went from this:

To this:

While Danks and Robin Ventura only referred to vague "mechanical changes" that month, Danks was more specific about the topic to Scott Merkin on Saturday:

"Our thought [on the lower leg kick] was to cut out as much movement, just because when I get my leg up high, it gives me a chance to fly open, get off balance, which hurts my command," Danks said. "And it flattens the ball out, which we both have seen isn't a good thing."

That much seemed evident, especially with his changeup. He gave up just one homer in September, which matched his first month of the season in terms of stinginess. Probably not by coincidence, his changeup stayed down in those months:

So that checks out, more or less. However, Danks says another tweak helped put a dent in his homer total:

"The lower arm angle is intended to help me get some sink on the fastball, which keeps me down in the zone, gets me more ground balls," Danks said. "It keeps the ball in the ballpark, and you know, it's feeling great right now.

"I'm excited about it. It's only going to help and it feels like it's closer to my consistent arm angle."

With this, the effect is far more visible than the cause. His ground-ball rate jumped up close to 50 percent over his last handful of starts. However, Brooks' data shows a pretty consistent vertical release point throughout the whole season.

That's not to say Danks is wrong. Maybe his arm angle is lower, but his hand ends up at the same spot because his upper body is more centered. Or maybe he's describing a feeling more than fact. Placebos have their place.

But this is a spring training story, so we have to adjust for a certain (and welcome) level of optimism. When the rubber hits the road, I'm guessing the shortened windup will hang around, because it didn't cost him any velocity. The success with grounders seems more fleeting. I'm thinking the combination of improved command and not-particularly-powerful opponents (and fatigued ones at that) resulted in more grounders over his last four starts, and I'd expect the ball to start leaving the park more often than he'd like in May and June. His fight with regression is usually a tooth and nail one.