A First Look at Steven Matz

The Mets have an embarrassment of riches in their starting rotation. Jacob deGrom has seemingly become one of the best pitchers in baseball, and Matt Harvey has pitched very well in his first half-season since returning from injury. Behind them, Noah Syndergaard has shown flashes of dominance over his first eight starts in the majors, while Bartolo Colon and Jon Niese have pitched admirably at the back of the rotation. To accommodate all of these arms, the Mets outrighted Dillon Gee — a pitcher who appears to be a serviceable starting pitcher — to the minors last week.

Yet, despite of all of the talent in their rotation, the Mets are adding yet another intriguing arm to the mix. Word broke yesterday that New York is summoning lefty Steven Matz to the majors. He will make his big-league debut on Sunday against the Cincinnati Reds. The Mets will presumably employ a six-man rotation for the time being. Kiley McDaniel ranked Matz 65th on his preseason top-200 list.

Matz certainly did enough in the minors this year to warrant a call-up. In fact, if it weren’t for the current log jam at the big-league level, he likely would have gotten the nod a bit sooner. Matz pitched to a 2.19 ERA and 3.43 FIP in his 90 innings in Triple-A Las Vegas. He struck out an impressive 26% of opponent batters faced, while walking a reasonable 9%.

Given his ERA and FIP differential, it’s probably safe to say that Matz has gotten a little lucky this year; however, it’s also worth noting that he’s outperformed his peripherals at every minor league stop. In his nearly 400 minor-league innings, he’s undershot his FIP by 0.68 points, so he very well might be one of those guys who consistently outperforms his peripherals.

Those numbers would be notable coming from any pitcher, but they’re especially impressive considering Matz’s environment. Matz pitched in the Pacific Coast League, which is notoriously conducive to run scoring. The PCL has averaged 4.7 runs per game this year, trailing only the High-A California League by this metric. Not only did Matz pitch in the PCL, but Matz has also had the misfortune of playing half of his games at Cashman Field: the Las Vegas 51’s bandbox of a stadium. Even in the hitter-friendly PCL, the 51’s consistently place at or near the top of the league in run scoring. And that’s mostly due to the team’s home ballpark.

All and all Matz looks pretty good, but there’s one possible knock on him: his age. Matz is 24, which isn’t particularly young for a player who’s just now making it to the majors. Most prospects worth their salt are already in the majors by Matz’s age, but Matz has just a half-season above Double-A. And he has just two half-seasons — or, more eloquently, one season — above A-Ball.

A player’s age relative to his level is important, but it’s also necessary to take a step back when using it as a barometer for prospect evaluation. There’s often a good reason that a prospect is older than many of his peers, and Matz is a prime example of this phenomenon. Matz  got a late start to his pro career after essentially sitting out three full seasons (2010 and 2011 plus most of 2009 and 2012) while recovering from Tommy John surgery. Jason Parks wrote about this very phenomenon with regard to Matz last July, shortly before Parks landed a job with the Chicago Cubs.

What I failed to properly contextualize at the time was that Matz’s life age was much older than his baseball age, as he missed two full seasons dealing with the elbow injury, surgery, and the subsequent recovery process. The 22-year-old in Low-A was really just a high school arm with a college birth certificate, a pitcher with only 29 innings of professional experience on his resume before his Sally League debut.

Two years later, Matz’s birth certificate still understates his point on the development curve. He’s not your average 24-year-old. So, before I go and run Matz’s numbers through the KATOH machine and the Mahalanobis machine, I think it makes sense to take his age-experience mismatch into account by adjusting his age down a bit. How much? I don’t know about you, but I’m feeling 22. Two years might seem like a bit much, but in practice, I’m hacking off closer to a year and a half: Matz’s May 29th birthday makes him a young 24 by baseball standards.

With this in mind, let’s get on to the number crunching. Plugging Matz’s adjusted age and minor-league stats into KATOH yields a projection of 7.6 WAR through age 28, which is quite good for a pitcher. Heading into the season, Julio Urias and Syndergaard were the only pitchers who received better forecasts.

Let’s get some comps up in here. Using league-adjusted, regressed stats, along with age (minus two), I calculated the Mahalanobis distance between Matz’s Triple-A performance and every Triple-A season since 1991 in which a pitcher faced at least 350 batters. Below, you’ll find a list of historical players whose performances were nearest and dearest to Matz’s, ranked from most to least similar.

Rank	Mah Distance	Name	IP thru 28	WAR thru 28
1	0.44	Rich Harden	845	15.6
2	0.46	Ruben Quevedo	326	0.0
3	0.48	Cal Eldred	661	8.2
4	0.62	Dana Eveland	392	3.2
5	0.65	Allen Webster*	104	0.0
6	0.79	Scott Elarton	716	4.3
7	0.81	Hayden Penn	82	0.0
8	0.84	Aaron Myette	154	0.0
9	1.00	Matt Harvey*	331	9.6
10	1.00	Anthony Reyes	293	1.3
11	1.02	Jake Odorizzi*	281	4.2
12	1.02	Dan Reichert	395	1.6
13	1.04	Joaquin Benoit	464	4.0
14	1.06	Kyle Weiland*	42	0.0
15	1.13	Sam Militello	69	0.4
16	1.14	Arthur Rhodes	569	6.7
17	1.14	Gavin Floyd	959	12.1
18	1.20	Renyel Pinto	231	0.0
19	1.23	Kurt Ainsworth	126	0.7
20	1.23	Gio Gonzalez	1,089	18.0

*Pitchers who have yet to play their age-28 seasons.

Rich Harden, Ruben Quevedo and Cal Eldred are the three who performed most similarly to Matz when they were on the cusp of the major leagues. Harden was an excellent, but injury-prone pitcher in his early- and mid-20s before the barrage of injuries finally pushed him out of baseball at age 29. It’s reassuring to see his name at the top.

I’d also put Eldred in the success bin, as he had a respectable run with the Brewers in the 1990s. Quevedo, on the other hand, was a pretty big flop. Although, I think it’s fair to say that Quevedo had nowhere near the suff that Matz does. The limited PITCHf/x data on Quevedo indicates that he averaged 87 and 85 mph with his fastball at age 23 and 24. Behind that front trio, we see guys like Dana Eveland (what’s with all the erstwhile Brewers?) and Scott Elarton, who both had snippets of big-league success. The Matt Harvey sighting is also an encouraging omen for Mets fans.

Along with Harvey, deGrom and Syndergaard, Matz makes four young young and promising pitchers in the Mets rotation. Odds are, Matz’s performance won’t quite match what that trio has produced, but he still figures to have a quality career ahead of him. Injuries halted his development in his early years as a pro, but he’s done nothing but dominate since he returned to the mound. Now, six years later, he’s finally made it to the show. And all signs point to his minor-league success carrying over to the big leagues.