Revisiting the Case of Doug Fister's Velocity

Last week I wrote an article discussing Doug Fister's sudden uptick in velocity that was closer to the velocity that he showed in his successful seasons. It appeared to be that some tinkering with his mechanics were to credit as he looked to have a little bit better drive to the plate improving momentum. That momentum allowed for a quicker delivery and a softer front side.

However, that velocity wasn't present in his next start. That begged the question of whether his mechanics regressed or if I was flat wrong. Being wrong wouldn't be the first time and it definitely wouldn't be the last. There's also one other possibility. Pitch f/x cameras are not perfectly in tune from park to park. The attendance can weigh down the stadium slightly and adjust their accuracy. That's why they are re-calibrated mid-season. So, it simply could have been that the cameras in Oakland measured him faster.

But, let's take a look anyway.

This is from the start against Seattle on May 6th, his most recent start. It looks very similar to his start with the best velocity (shown below).

The camera angle is a little different and can create some perception differences.

Here is the max knee height position in his most recent start.

He looks a little straight in that back leg. Now compare it to the Oakland start.

The camera in Houston is closer to CF which should give a slightly better look at how flexed his knee. So, it looks straighter in Houston, so it is likely to be a little more straighter.

Now, lets look at how he decelerates.

Compared to the Oakland start.

Given the frame speed, I'd say is pretty similar. The back leg looks different but is mostly just timing of the frame.

Now, the last part we looked at in the original article was the pace of his delivery from max knee height to release point. In the Oakland start, it took eleven frames. In his most recent start, twelve frames. Not a huge difference. Really the back leg is the largest change, and it's not a big one.

So, what gives?

Take a look at this chart on his velocity.

brooksbaseball.net

That single plot on his four-season in his most recent start looks very similar to the Oakland start. In fact, it's 0.14 mph higher. So the velocity was present in this game.

BrooksBaseball.net makes adjustments to pitch classification following the game. The raw data from MLB Advanced Media classified thirty of his fastballs as four-seams. Brooksbaseball.net adjusted it to just one. So, some of these differences could actually be something to do with the three fastballs he throws and how they're being classified during the adjustments. Some misclassified cutters can bring the average down. Some misclassified four seams into two-season could bring the sinker average velocity up.

One start is just too little information to gather true conclusions on. But, the leg did seem straighter and it did seem to be slightly slower of a delivery.

It was also brought up that it would be a good idea to compare his delivery to past seasons. So, here is his delivery from 2015. A season where he averaged 86-87.

He had a pace of 13-14 frames. But, take a look at his max knee height position.

Pretty straight and very similar to early 2016 season Fister. Not much turn and not much drive with the hip.

Here's a significant thing too look at. He's very flexed in his front leg with very little stability. By not extending the front leg he loses some of the energy created by momentum. The energy is leaked at the hips and doesn't flow up the chain.

Now compare to his his 2013 season where he averaged 90 mph and put up his highest WAR numbers.

His pace is about 12-13 frames, so just slightly quicker.

Just slightly more bend than 2015 and similar to the Oakland start here with his balance leg. But, here's the big difference, look at his max knee. It's much higher than any other clip. That high knee allows him to build more momentum when he gets headed towards the plate. If used properly of course because it can also create timing issues.

Look at his front side in the clip above. This still frame is just a moment in time but helps to illustrate how much less firm his front side is than 2013 or early this season.

Fister's start at Oakland was the closest to the 2013 delivery but still lacks the momentum toward the plate created by his higher leg kick. He also not as soft on the front side but his delivery is trending that way.

I also had the question if more momentum can lead to control issues. And the answer isn't yes or no. It can for somebody who is used to a slower delivery because they have to get a feel for their release point at a different timing. But, for a pitcher who has been struggling to have the momentum they need for their delivery and they find it, it can help. Considering the slower delivery for awhile now, I would say that a quicker delivery could potentially diminish control in the short term.