Wednesday, March 23, 2011

A Closer Look At Kevin Slowey


For me, it’s hard to get immediately on-board with the Free Kevin Slowey movement. I suppose you could say I'm flying stand-by. 

Yes, without question, I believe that a healthy Kevin Slowey is a far superior option in the rotation versus the likes of Nick Blackburn. Across the board, Slowey has put up better numbers at the major league level. His opponent on-base percentage is lower as is his walk rate. He’s got a far better strikeout rate, demonstrating the ability to retire hitters without waking his defense. The statistical analysis of the two puts Slowey light years beyond Blackburn’s capabilities.

While Dave Cameron jotted all of those explanations down in a post yesterday, all of which – if you think along statistical lines – surely made you nod your head in agreement but, to me, it felt that his write-up did not paint the entire picture of the situation.

Undeniably, based upon Slowey’s numbers and minor league track record, it is easy to reach the conclusion that Cameron’s presenting. Slowey’s incredible strikeouts-to-walk ratio is worth salivating over by any GM. Yet, he seems to skim over the larger issue and that was the fact that hitters received the ball on a tee this year. There was little deception, just guile.

While he alludes to the fact that the Twins right-hander is susceptible to the long ball, saying he gives up “a good amount” of home runs, Cameron more or less glosses over to what extent Slowey’s been taken yard. Over the course of the same period of time Cameron cites Slowey’s impeccable strikeouts-to-walks ratio – noting that it is better than all but three high-quality hurlers – he fails to mention that his home run rate per nine innings is also near the top of the list. His 1.28 home runs per nine innings is currently the seventh highest since 2008 among those with a minimum of 400 innings.  To his credit, because he is so miserly with the walks, a small majority of those round-trippers have come with no one on base (48 of 74 career home runs allowed) so the damage is usually minimal.

That said, last year we saw somewhat of a different version than the one that had accumulated most of those stats dating back to 2007. This version of Kevin Slowey saw a decrease in pitch movement.

In 2008, pre-wrist surgery, Slowey appeared on the cusp of becoming an elite pitcher in the American League. That season, he three complete games including two shutouts on his way to 13 quality starts in 27 outings. What’s more is that he dominated right-handed opponents. In addition to holding them to a .637 OPS against, he posted a stupid good 57-to-3 strikeouts-to-walk ratio. Fast forward to a season removed from wrist surgery and Slowey struggled some to subdue the same-sided hitters. Righties produced a .807 OPS off of him while launching 15 home runs (opposed to nine in ’08) while he held a much more reasonable but still very good 49-to-11 strikeouts-to-walks ratio. Slowey still threw strikes in bulk; only now his secondary pitches weren’t getting the same break as they had been two years prior – perhaps a lingering side effect from the wrist surgery.

Slowey’s slider, his main secondary offering to right-handed foes, was not getting the same downward bite it showed in 2008. Below are two of the heat maps found at Fangraphs.com that shows the location of his sliders against right-handed hitters. As you can see, in ’08 (on the left) Slowey placed his slider down-and-away in the zone. This past season (on the right), Slowey’s slider had a much higher tendency of staying up and in:



To provide more flavor, here are two isolated samples showing the different trajectory of Slowey’s sliders to provide you with an idea of the movement (or lack thereof). In the first clip, Slowey’s 2008 slider has great downward dip, falling under the swing of the Royals Miguel Olivo. In the second clip, Slowey’s slider fails to drop as the Mets’ David Wright tears it down the left field corner for a double:

2008 - via MLBAM

2010 - via MLBAM

What Slowey throws to Wright is your standard, run-of-the-mill cement-mixer slider. While it shares the same velocity to the one in 2008 (85 miles per hour), it had on average an inch less vertical drop. When you have a pitch with less drop and a mid-80s velocity, this gives the hitter ample opportunity to square up on the ball. And square up they did.

Because of the location, the results were extremely different, particularly in the groundball department:

Slowey’s slider versus right-handed opponents

% Thrown
Miss%
GB%
OPS Against
2008
18%
28%
41%
.608
2010
16%
23%
29%
.710
 (via Inside Edge)

With a decline in grounders from this pitch, Slowey’s ability to keep right-handers from taking flight on him all but disappeared. In ’08, right-handed opponents took to the skies just 43% of the time. This past year, they went airborne a whopping 53% of the time – the highest amount by a non-left-hander.

In addition to his surgically repaired wrist, there was a noticeable difference in Slowey’s follow-through which may have been another factor in his loss of movement or at least somewhat responsible for his late season arm ailment.

These clips, from a start against the Brewers then one in Oakland back in 2008, shows a powerful and fluid back leg push from the rubber with an almost pendulum swing of his leg on the follow-through:




This was when his fastball was a devastating weapon with a decent amount of velocity in the low 90s with some sick movement to boot. That season, Slowey’s fastball was 13.4 runs above average according to Fangraphs.com. Somewhere between 2008 and last year, Slowey abandoned this motion. Compare that to his follow through from his May 2010 start in Cleveland. In this instance, his back leg follows a more deliberate and methodical pattern:



Why the change?

My assumption is that based on the way the first follow-through rendered him almost unable to field his position (a similar knock on Liriano), the run-in with Juan Uribe’s line drive possibly made him alter his follow-through in order to put him in a better position to field (or avoid) lined shots. Under that circumstance, it makes complete sense to adjust. However, overall fastball movement and stamina may have come at the expense of the alteration.

Then there was the issue of the sore right tricep which landed him on the DL from August 22 through September 9.  While culling through video clips, I notice that in his start against Tampa Bay on August 5, the day before reporting the sore elbow, Slowey went so far as to make some fairly abrupt stops in his follow-through:





It hurts my arm watching these clips. You can see why he may wind up experiencing tricep discomfort. Slowey discontinues his motion altogether, putting a lot of strain on the arm.

These two factors working in conjunction – losing his slider or not engaging his lower-half – may have led to his inability to get himself through the prerequisite innings last year in order to qualify for that quality start that Ron Gardenhire desired. Without his slider, Slowey had troubles retiring righties regularly, most likely leading to more pitches in the early innings. Likewise, by not engaging his lower-half, Slowey likely tired out his arm sooner as well as added pressure on his elbow which culminated in a bout of tendinitis.  

You have to wonder if the coaching staff watched him throughout the spring and decided that he needed more time to work out some of the kinks. Like get his slider back or try to engage his lower-half more in his motion. If that happens to be the case, it’s not irrational for the coaching staff to have him work on these areas in the bullpen rather than the starting rotation.

While Slowey’s stuff actually took a significant step backward – leaving him exposed to right-handers - his precision tuned command guided him through the 2010 season. At least to the point where he was able to amount respectable peripherals despite hitters elevating more of his pitches. If you were trying to predict his 2011 season on the peripherals alone, you would have to assume that he was going to have a better year. It is possible that he needed just a year to get used to the new sensation in his throwing hand, that 2011 will witness a renaissance of movement in his pitches.

Until he proves otherwise, there is no harm keeping him in the bullpen until he pitches his way into the rotation or someone pitches their way out. 

11 comments:

SethSpeaks said...

In my opinion, for Slowey, it's all about consistency with his secondary pitches. I agree that has been the issue. He put up solid numbers when healthy last year despite the fact that I didn't see a lot of really good sliders or changeups. I think he can be very good, but I don't think spending a little bullpen time is necessarily a bad thing for him or the team.

OB said...

there is no harm keeping [Slowey] in the bullpen until he pitches his way into the rotation or someone pitches their way out.

That's where I'm at too. Slowey's pinpoint control remains elite. His time will come just so long he don't get pushed out the door.

Paul said...

Parker, I'm always excited when a many-thousand word post from OTB shows up on my RSS feed, because I can always count on it being a unique, well-reasoned perspective and I usually learn something. This post was no exception, keep up the good work!

Ben said...

Great read

jimbo92107 said...

The first two clips don't even look like he's trying to throw the same pitch. Are you sure the second one is supposed to be a slider? How can you get downward movement pushing the ball upward with the palm of your hand? How can you keep the ball down in the zone without finishing low?

Maybe it's because his wrist was too stiff or it hurt, but it looks to me like Slowey was trying to get by last year without using his wrist as a loose hinge. The movement he was getting pre-injury was coming from using his wrist as the end of a whip action, which gets spin and downward movement on his pitches.

Post-injury, it looks like he's reverting to a short-arm delivery that resembles an infielder's throw. Accurate, but little movement. No wonder he's getting rocked. He's throwing the ball like a shortstop. If Slowey wants to get back the old magic, he'd better remember how to fling the rock like a trebuchet. Easier on the arm, and you get a lot more movement.

Twins said...

The first two clips don't even look like he's trying to throw the same pitch. Are you sure the second one is supposed to be a slider?

Yes, I can say with the utmost confidence that the pitch you see in the second clip is him trying to execute a slider. I culled through numerous clips and found there to be similarities in this clip with other sliders thrown this year.

You can't see it, but Slowey throws this pitch at 85-mph - his typical slider speed. Additionally, based on the spin, pitch f/x also labeled this offering a slider.

I believe that you are correct in attributing the source to the wrist. The optimistic viewpoint is that it was just him having a sore or stiff wrist and that he'll be able to adapt next year. Pessimistically, it could be that he'll never have the full range of motion in his wrist now that he has screws placed it in. Personally, I hope it is the former and not the latter.

Anonymous said...

Great post

marshall mathers said...

the pitch to david wright is a front door cutter, a pitch slowey started throwing just last year...which also explains his slider heat chart...front door cutter/slider is a difficult pitch for a pitcher to execute, but is equally difficult for a hitter to react to..check out some of his strikeouts from last year..arm side sliders..

Twins Fan c.1981 said...

@marshellmathers - Not dismissing your theory but I did not find any evidence to support that he was adding another pitch last year (at least by pitch f/x and my internet searching)...I think you could be on to something - that he was trying to get his slider in under the swing of right-handers more often this year, but demonstrated an inability to get any form of drop on it or keep in lower in the zone. However, if you look over his slider locations in '08, he threw plenty of inside sliders to righties, just not at the same elevation...My response to that would be that if he was intending on locating the pitch there, he needs to either refine it or discard it. Looking over the batted ball results of his slider, it is only hurting his outcome.

Robert said...

Zero chance he is throwing a slider in that second clip.

cmathewson said...

Whatever that pitch was, it was high, inside, flat and slow. I saw Slowey get away with a lot of those last year. I also saw him not get away with a lot of them.


He's never had consistently great secondary stuff. The presumption always was he would continue to progress and improve on it. Last year, he took a step backwards. Hopefully, it was mostly mechanical, and he will make the adjustments. But I agree with Parker. There's no harm in him making those adjustments on the side instead of in games.

Until then, Blackburn has a better chance of being a workhorse than Slowey. And Slowey has a better chance of being successful in the bullpen than Blackburn. The decision makes sense.