Marcus Stroman overcoming his knee injury to pitch again in the 2015 season is an interesting storyline. It has also been talked about to the point where there's nothing more to talk about, really. Marcus Stroman disproving the doubters who thought he was too small to be a starting pitcher is also an interesting storyline, but has likely been discussed to death. While Stroman's mental make-up can't get enough praise, it would be a disservice to Marcus if we didn't also credit him for his amazing brand of pitching. And when I say amazing, I do mean that scientific research will prove that Marcus Stroman is the most interesting pitcher in the game of baseball.
My argument for Marcus Stroman as "Completely Objectively Most Marvelously Interesting Thrower", or COMMIT, is based on simple mathematics. A lot of pitchers have a specialty pitch, and sometimes that specialty pitch is incredibly interesting because it does something better than all other similar pitches. Example one: Marco Estrada and his "rising" fastball, because it has more rise than any other pitcher's fastball. R.A. Dickey's angry knuckler, for obvious reasons. Marcus Stroman has at least two, potentially three pitches that have a shot at being called the best in the game at what they do. Three is more than one, so by virtue of simple math I have hereby scientifically proven that Marcus Stroman is the most interesting pitcher of our time.
The 'retro' sinker
If you've seen Marcus Stroman pitch this season, you will have seen him throw his sinker. You will also have seen that pitch sinks a lot. The pitch has been so effective that I've had to rethink my position on sinkers and two-seamers. Previously, I didn't care for distinguishing between sinkers and two-seamers, because they seem to be largely the same pitch. But when you throw a sinker that drops more than James Shields' ridiculous circle change, I think you've earned the right to call your two-seamer a true sinker. Defying the laws of physics should be rewarded, and Stroman's sinker drops an inch more than the aformentioned Shields circle change, also an inch more than Roy Halladay's sinker, and about three inches more than the sinker thrown by a certain Felix Hernandez. (source: Brooks Baseball)
While listening to FS1's coverage of the Astros-Royals series, I heard A.J. Pierzynski (I think) say that there used to be more sinker pitchers who threw in the high-80s, while MLB currently seems to be populated with pitchers throwing mid-90s four-seamers. And I certainly share that feeling, with no more Derek Lowe, Chien-Ming Wang, Brandon Webb or even Aaron Cook in recent years. With Tim Hudson retiring and Justin Masterson ineffective, it seems that there is no starting pitcher able to seriously challenge Marcus Stroman for having the sinkiest of sinkers. There are some semi-effective National League pitchers - Charlie Morton, Chris Heston and Mike Leake - that could make a claim, but Stroman's sinker seems to have the edge in effectiveness. Marcus Stroman's sinker compares favourably to that of one of the best sinkerballers of our time in the form of Tim Hudson, and that should be enough to tell you that the sinker is quite amazing, indeed.
The frisbee curveball
The first pitcher that came to my mind when I saw the movement on Marcus Stroman's curveball was the breaking ball thrown by Bronson Arroyo. Now, that may not seem very flattering to you, especially if you've read Jeff Sullivan's set of pitch comps, which likened Stroman's breaking ball to those thrown by elite pitchers Jose Fernandez, Corey Kluber and Yu Darvish. Secretly though, Bronson Arroyo's curveball might be up there with those insane breaking balls, as it's a pitch that has single-handedly made the soft-throwing Arroyo an average major league starting pitcher over his career. According to Fangraphs' pitch values, Arroyo's breaking ball has been 156 runs better than average over his career, compensating for a very pedestrian set of fastballs that have been worth -116. On a per pitch basis, Bronson Arroyo's breaking ball scores better than a Madison Bumgarner slider. And yes, the slider is Madison Bumgarner's best pitch.
So, lofty comparisons all around for Marcus Stroman's sweeping curve/slurve/breaking ball. Is it the best in the game though? Corey Kluber's 'slider' has more horizontal separation between his two-seamer and his breaking ball than Stroman does, with incredibly similar velocity separation and a lot more vertical separation. It's the lack of vertical drop compared to the sinker that makes a Bronson Arroyo comparison relevant, although Arroyo's curveball is also really, really slow. I don't know if combining a lack of relative vertical movement with high velocity is beneficial to a sweeping curveball, but if it is then Marcus Stroman is the best at creating such a pitch. He also throws his curveball with less drop than his slider, which is incredible, fascinating, and - as far as we know - unique among starting pitchers.
The sneaky cutter
When watching a game of baseball, the most spectacular pitches thrown are probably the big looping curveballs (Clayton Kershaw and Adam Wainwright come to mind), devastating changeups and sliders, and sinkers with amazing movement. The least spectacular to watch might be the cutter, as its movement is quite hard to pick up on television. But the cutter most assuredly does not have less potential than any of those other pitches. Ask Roy Halladay, who threw over 40% cutters towards the end of his career, more than any of his other pitches. Here's a great look at a great cutter from Roy Halladay in the 2011 NLDS, and here's a look at one of the front door variant. Only slowed down and zoomed in is the true potential of a great cutter visible, as the many victims of Roy Halladay would likely tell you.
The reason Marcus Stroman's cutter reminds me of Roy Halladay's cutter - quite possibly the greatest cutter of our time not thrown by Mariano Rivera - is because of how its movement relates to that of his sinker. The pitchf/x numbers tell an interesting story:
|Pitcher||Velocity diff||Vertical diff||Horizontal diff||Whiffs/swing||Fouls/swing||Groundball%|
|Stroman||-1.7 mph||2.02 in.||7.87 in.||16.5||44.9||64.0|
|Halladay||-1.7 mph||1.85 in.||7.25 in.||16.9||44.2||44.3|
|Beckett||-3.3 mph||0.45 in.||9.19 in.||24.6||40.8||36.2
|Cueto||-3.9 mph||-1.35 in.||7.62 in.||15.0
I included Josh Beckett and Johnny Cueto because Jeff Sullivan found their cutters to be most similar to Marcus Stroman's. I think this table disagrees. Most pitchers have slower cutters than Roy Halladay, but not Marcus Stroman. A lot of them have cutters that drop more than their sinkers, but Halladay and Stroman seem to care more about the horizontal movement on the cutter. The two cutters could almost not be more similar, the groundball rate seemingly the only significant difference.
The big question with Marcus Stroman's cutter is "will he trust it"? In his seven appearances in 2015, Stroman threw the cutter just 10% of the time, a far cry from Roy Halladay's 40%. In the pitchf/x era, Roy Halladay threw the cutter for a strike 72% of the time, Stroman in 2015 just 61%. Then again, hitters went 1-for-10 when hitting Stroman's cutter in play, with 0 extra base hits, so it was definitely a good pitch for him when he did throw it. The potential is definitely there, and it will be interesting to see if Stroman can show his cutter's true potential to the world of baseball in the near future.
Are you kidding me?
Combining Roy Halladay's best pitch with Tim Hudson's best pitch and adding Bronson Arroyo's best pitch to create one super pitcher sounds like something they would do in a movie like Jurassic World. You know, where they create a super dinosaur with all kinds of abilities that don't necessarily belong on one single dinosaur. Marcus Stroman, the baseball equivalent of such a super dinosaur, appears to be very much a real person, not a work of fiction. And Toronto Blue Jays fans will likely get to watch him in action for at least five more seasons. That should be fun.