Is Blackburn having mechanical issues?

Tuesday night’s game witnessed a significant deviation from what has become expected of Nick Blackburn since his recall.

After being sprung from the boondocks of northwestern New York, Blackburn had consistently enticed opponents to beat the ball into the turf. With the exception of one start in Seattle, the Twins right-hander has been able to coerce more groundballs than fly balls -- groundball’s less attractive cousin. This was a strong indication that he had rediscovered his sink on his two-seamer, one of two tasks he was asked to perform when he was sent back down to Rochester.

This departure from the recent batted ball results may raise (tiny) flags for the Twins anticipated fourth starter in the postseason:

Nick Blackburn’s batted ball distribution
	Groundballs	Fly Balls	Line Drives
8/25-9/22	86 (53.4%)	54 (33.5%)	21 (13.0%)
9/28	6 (30%)	11 (55%)	3 (15%)

Obviously, this is an insanely small sample size to draw any real conclusion however several questions can be present that examines why the results differed so greatly from the rest of September.

As noted above, during his demotion Blackburn was directed to work on two things that had been hindering his season: his off-speed stuff and his mechanics.

Since returning to Minnesota, Blackburn has enhanced his variety and changed his speeds extremely well. Likewise, his polished mechanics has led to additional sink on his two-seamer. This combination had yielding a tremendous stretch of starts in which Blackburn had posted a 1.97 ERA as opponents appeared flummoxed at the new-look Nick.

Unfortunately, the Royals put the kibosh on that feelgoodery.

While still working in his changeup and curveball, staying true to his newfound art of variety, Blackburn was roasted on his two-seamer as Kansas City smeared that pitch across the Missouri night sky. With opponents elevating his two-seamer all over the place, this raised the issue of whether or not his mechanics had retreated to his pre-demotion days.

Following Tuesday night’s outing, Blackburn dismissed that sentiment:

"I'm really not concerned about what happened tonight. Obviously, I'm not happy about it, but I'm not too concerned. I've been throwing the ball well lately. My mechanics -- didn't feel like there were any issues there. That's been my problem the whole season whenever things aren't going well. Tonight I just wasn't hitting spots."

In a contrast to what the starter would say, during the FSN postgame show, Robby Incmikoski noted that Ron Gardenhire told reporters in the clubhouse that pitching coach Rick Anderson noticed something in Nick Blackburn’s delivery that may have influenced his ability to get the proper sink on his fastball and thus incite grounders.

Without access to the video of the start (TwinsBaseball.com posts only “highlights” and this start was anything but), examining the pitch through MLB.com’s pitch f/x system might be the next most telling data source.

Reviewing the movement at TexasLeaguers.com, we can see that there is a discrepancy in the overall “downward” movement of his two-seamer. As a primer, below is Mike Fast’s introductory chart of how pitches should move based on their spin. In short, the lower the area, the more “downward” action a pitch has (splitters and changeups have this sort of motion). Similarly, the more the pitch winds up to the right of the axis, the more lateral movement a pitch has (hence sliders, curves and cutters are typically to the right of the axis).

During his tumultuous early season struggles, Blackburn’s main pitch, the two-seamed fastball, had little drop in it on Tuesday night:

Granted, this pitch reflects the type of movement a two-seamer is supposed to have, yet it is not the same motion it has when Blackburn has his varsity squad two-seamer working. This type of movement was very reminiscent of his pre-demotion days:

Now compare those two to the drop of his two-seamer from August 25^th onward:

Clearly, Blackburn’s two-seamer had far less drop on it than it had in the prior six starts. Given Rick Anderson’s ability to diagnose pitchers well, it is likely that something went astray in his mechanics causing the sinking fastball to stay up in the zone.

For Blackburn, the question is whether this is a slight mechanical hiccup or a complete derailment from his progress established since returning from Rochester. As a pitcher on the bubble for being a spot in the playoff rotation, Blackburn has one more start left to prove that it was the former rather than the latter.