New York Mets rotation: Who has the best repertoire?

Who is the ace of the staff? Who should take the ball on Opening Day? Whom would you want pitching Game 7? These are the types of questions New York Mets brass and fans alike are fortunate enough to have with their young pitchers: Jacob deGrom, Matt Harvey, Noah Syndergaard, Steven Matz, and Zack Wheeler*. The 2015 season gave the Mets their first opportunity to have four of the five together in the rotation at the same time. Wheeler is due to return at some point this summer from Tommy John surgery.

*Editor's Note: We all know this is just fighting for second place behind Bartolo Colon.

The question this article will examine is: who, of these five young arms, has the best repertoire? Using PITCHf/x data from brooksbaseball.net, we will look at each pitcher's fastball, changeup, slider, and curveball. The average release speed, whiff percentage, and batting average against will be taken into account to examine each pitch. For deGrom, Harvey, Syndergaard, and Matz, the 2015 data will be used; for Wheeler, the 2014 season will be used since he missed the 2015 season.

Fastball

Player	FB Avg. Release Speed	Whiff %	BAA
Jacob deGrom	95.8	13.3	0.182
Matt Harvey	96.5	10.3	0.247
Noah Syndergaard	97.8	11.0	0.224
Steven Matz	94.6	8.2	0.278
Zack Wheeler	96.2	10.3	0.263

Noah Syndergaard has the edge in terms of average release speed, as his fastball is 1.3 mph faster than Matt Harvey's. All five pitchers clearly have the ability to overpower hitters with their fastballs, all of which reach the mid-90s. In terms of having a fastball that misses hitters' bats, Jacob deGrom was clearly above everyone else with a 13.3 whiff rate. This probably speaks to the effectiveness of his offspeed pitches, which we will examine later in this article. Besides an overpowering fastball, a pitcher needs to have effective offspeed pitches to have the ability to make batters swing and miss.

As if the best whiff percentage wasn't enough, deGrom's fastball produced the lowest BAA, and it is not even close. Batters hit only .182 against deGrom's fastball, the only pitch to have a BAA under .200. Once again, Syndergaard is next closest at .224. In each category (whiff rate and BAA) deGrom and Syndergaard finish one and two, respectively.

The average release speed of Harvey's fastball decreased only 0.5 mph from his 2013 velocity of 97.0. 2015 was his first season removed from Tommy John surgery, so Harvey could see a slight increase in velocity as he moves further away from the procedure. On the other side of the spectrum, when Zack Wheeler returns from his Tommy John surgery, he may see a decrease in his fastball velocity this season.

Verdict: Best Fastball - Jacob deGrom

Changeup

Player	CH Avg. Release Speed	Whiff %	BAA	Diff. from FB
Jacob deGrom	86.2	23.6	0.148	-9.6
Matt Harvey	88.8	16.2	0.235	-7.7
Noah Syndergaard	88.9	18.2	0.241	-8.9
Steven Matz	83.9	14.8	0.150	-10.7
Zack Wheeler	89.2	9.3	0.267	-6.9

When looking at the average release speed of a changeup, I wanted to combine it with the difference from the mph of each pitcher's fastball. Following this method, we see the largest release speed differential belongs to Steven Matz. His changeup average release speed is 83.9 mph and more importantly is 10.7 mph slower than his 94.6-mph fastball.

Once again in terms of whiff percentage and BAA, Jacob deGrom comes out on top. deGrom's whiff percentage is head and shoulders above the rest of the staff, as Syndergaard's 18.2 percent is next closest. BAA is much closer, as deGrom's .148 barely edges the .150 of Steven Matz. As I stated earlier, the effectiveness of deGrom's off-speed pitches, which we can see here, helps lead to the effectiveness of his fastball.

Verdict: Best Changeup - Jacob deGrom

Curveball

Player	CB Avg. Release Speed	Whiff %	BAA
Jacob deGrom	82.2	15.0	0.226
Matt Harvey	84.3	16.4	0.189
Noah Syndergaard	81.2	19.2	0.180
Steven Matz	77.6	10.6	0.222
Zack Wheeler	79.6	14.1	0.148

Steven Matz once again shows a stark contrast in release speeds, as his curve is about 17 mph slower than his fastball. The hardest curve belongs to Matt Harvey, with deGrom a close second.

The curve of Noah Syndergaard stands out when it comes to making bats miss. His whiff percentage is almost three percentage points higher than Matt Harvey's. However, Zack Wheeler had the lowest BAA, which is an intriguing facet of Wheeler's game to watch as he returns this summer — can his curveball achieve the same success against hitters, post-Tommy John surgery?

Of all the pitches, the curve has been the closest in terms of whose is best overall. Even though they are close, "Thor's Hammer" edges out the rest of his rotation counterparts. Combining his high whiff percentage and low BAA (Wheeler's may have been lower, but the uncertainty of coming off of TJS leaves me hesitant), Syndergaard has the best curveball on the Mets staff.

Verdict: Best Curveball - Noah Syndergaard

Slider

Player	SLD Avg. Release Speed	Whiff %	BAA
Jacob deGrom	90.3	13.9	0.261
Matt Harvey	90.3	18.0	0.188
Noah Syndergaard	88.6	24.4	0.095
Steven Matz	87.3		0.5
Zack Wheeler	90.0	14.1	0.231

The average release speed of the slider has no clear performer. There is almost no separation between deGrom, Harvey, and Wheeler. Steven Matz's slider numbers are skewed because he threw the pitch only 11 times, according to Brooksbaseball.net.

Syndergaard's whiff percentage blows everyone else's out of the water, but this number may be misleading. Syndergaard threw his slider only 86 times in 2015, compared to Matt Harvey, who threw it 428 times. While a whiff percentage of 24.4 is impressive, the low pitch count of sliders stops me from fully crediting the high whiff percentage. The same is true of BAA: Syndergaard's slider produced a BAA of .095, still an incredibly impressive mark, but a .188 BAA is more impressive given how many more times Harvey threw his slider.

Verdict: Best Slider - Matt Harvey

The Final Verdict

The debate of who has the best "stuff" is a fun one for Mets fans to have, and a legitimate case can be made for each of the five members of the Mets rotation. As I have previously stated, Zack Wheeler's repertoire will take time to return to form as he returns from TJS this summer. Steven Matz and Noah Syndergaard pitched partial seasons in 2015, so it remains to be seen if they can sustain similar performance for a full season. This study will be interesting to revisit this time next year, when Wheeler has returned and Matz and Syndergaard have a full season under their belt. Also, as Matt Harvey moves further away from TJS, his "stuff" should improve in sharpness and accuracy.

Overall, the pitcher with the best repertoire is Jacob deGrom. There is potential for Noah Syndergaard to have the best repertoire in the long-term, but for right now, Jacob deGrom is the ace.

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Carl Triano is a contributor at Beyond the Box Score.