Moving Robert Gsellman to the Rotation

After starting the season 11-1, the New York Mets have hit a bit of a skid in the road. They still sit atop a surprisingly robust NL East at a record of 16-9, but are running a 5-8 record since mid-April and are ranked substantially worse by expected record measures, generally seeing their performance as worthy of around a 13-12 record and fourth place in the East.

Still, they are where they are and where they are is pretty good. Talent-wise, the Nationals still look like the best team in the division – and should remain that way once more than half of their starters are in the lineup instead of on the DL – but there are two extremely promising up-and-comers in Philadelphia and Atlanta. Suffice to say, whatever window exists for the Mets to contend is small and immediate; they have a reasonably talented roster right now and need to win in the years between the Nationals’ post-2018 exodus of talent and the Phillies’ and Braves’ incoming deluge of prospects…if such an opening will even exist, and odds are it won’t.

This combination of unexpected opportunity, and the faint-but-growing sound of hooves on the horizon makes the relegation of top pitching prospect Robert Gsellman to the bullpen extraordinarily curious. Like other members of a surprisingly strong Mets‘ bullpen, Gsellman is off to an excellent start in 2018; he’s top 10 in WAR among relievers at 0.6 and boasts an excellent 32.8% strikeout rate, more than doubling last year’s 14.9%. In fact, despite throwing only 14 innings, he’s nearly equaled last season’s WAR output (0.7), which came across 119 innings and 22 starts.

Normally, we’d be looking at a Wade Davis situation: a mediocre-at-best starter gets moved to the bullpen, where he’s able to transition to a shutdown reliever, and shifting him back to the rotation actually causes him to produce less total value despite having many more opportunities. Davis’ 1.4 WAR in 135 innings his first season in Kansas City was the encore to a 2.43 ERA, 1.1-win campaign in his first season in the ‘pen and final season in Tampa. The Royals realized their mistake and ended up with a couple pennants and some nice rings.

The Mets, though, aren’t in quite the same situation. Let’s start with their current distribution of resources: they are 9th in SP WAR at 2.5 and 12th in RP WAR at 0.8, so they are generally getting more help than harm from their staff. But from that distribution, it seems like keeping Gsellman in the ‘pen is a better option, as it’s weaker relative to the rest of the league.

Thing is, Noah Syndergaard and Jacob deGrom have combined for 2.6 of that 2.5 WAR, which you’ll notice is actually a higher number. That means positions 3-5 in the Mets’ staff have combined for -0.1 WAR:

The Back of the Mets’ Rotation

Innings K% BB% ERA FIP WAR
Matt Harvey 21 18.1% 4.3% 6.00 4.75 0.1
Zack Wheeler 17 32.9% 3.6% 4.24 4.53 0.1
Steven Matz 21.2 27.4% 10.5% 4.98 5.44 -0.1
Jason Vargas 3.2 16.7% 8.3% 22.09 10.00 -0.2

There isn’t a lot of confidence to be had in those names. Wheeler (28) and Matz (27) aren’t as young as they once were, and they represent the options still possessing some upside. But we’re now more than three years removed from Wheeler being a good MLB pitcher – 2.6 WAR in 2014 – with a major injury in-between, and it’s difficult to suggest that he’s going to suddenly re-emerge as a rotation anchor. Matz was solidly above-average back in 2016, but didn’t pitch much last year and certainly didn’t pitch well when he did. Vargas is an innings-eater, at best.

Now that Vargas is off the DL, Harvey’s been moved to the bullpen, which is only where he belongs if you assume he belongs on a major league roster. Even if Harvey doesn’t take well to a relief role, the other side of the coin is whether the Mets’ bullpen can weather the loss of Gsellman, and the answer is likely yes. Closer Jeurys Familia is once again pitching like a top-five closer, but there’s more help than in years past. Paul Sewald has emerged as a viable setup guy, boasting a 1.55 FIP and 11.9% swinging strike rate despite throwing nearly half of his pitches in the zone. His slider-heavy approach means there will likely be more homers in his future than the zero he’s presently allowed, but his minor-league K/BB’s are sparkling and he only ever encountered home run troubles in the hitter’s paradise that is Las Vegas.

Former Marlins closer A.J. Ramos has had serious walk issues, but his 42.1% Zone% is higher than his career mark of 41.7%, and he’s really the veteran option in terms of depth. Because the Mets have a closer-in-waiting who was recently optioned to AAA in Jacob Rhame. Rhame’s stuff – a 95 MPH fastball, 87 MPH slider, and 86 MPH curve, all of which he throws at least fifteen percent of the time – is legit. Despite a 7.36 ERA and 10.00 FIP in his 3.2 innings this year, he generated a whopping 14.1% swinging strike rate off of a 53.1% Zone% – the guy lives in the zone and hitters still can’t make contact.

This is nothing new. Rhame’s minor league strikeout percentages have hovered between 25-30%, while he’s generally kept his walk rate under 10%. The numbers say he limits walks and gets strikeouts, and the other numbers say that’s sustainable. Rhame’s likely waiting for an opening now that Harvey has been moved out of the rotation, so he gives us a good fallback option in case there’s a need for right-handed relief help with the departure of Gsellman.

That means our boy can replace either Wheeler or Matz. Which one isn’t that difficult of a decision to make, actually, as the Mets’ bullpen currently features only one lefty in Jerry Blevins. He’s sporting an 88 MPH fastball and five walks against three strikeouts in five innings. Not good.

Serendipitously, Matz is likely more suited for bullpen work than Wheeler anyway. In five starts, he’s thrown only 21 ⅔ innings, making it into the sixth just once. Let’s check out his results in his third time through the order this year:

April 7th: BB, K

April 13th: K, E, HR, K

April 25th: HBP, BB

It’s a terribly small sample, but it includes three strikeouts, two walks, a hit batsman, and a home run spread across eight PA. The really significant numbers are the ones that aren’t there, namely all the batters the bullpen had to retire because Matz couldn’t get more than five innings into a game.

Just as importantly, Matz’ repertoire is likely more suited for relief than Wheeler’s. He’s got three pitches and really only has one effective pitch in the curve:

2018 Per-100 Pitch Values





Zack Wheeler





Steven Matz




So Wheeler can likely get away with his three-pitch mix, while Matz should be a far more effective pitcher when he can use his fastball to set up his curve. And now there’s a legitimate lefty relief option, leaving a spot open for a guy that hasn’t been discussed much, considering this whole thing is about him.

Let’s dig into Gsellman’s numbers by adding his line to the above table:





Robert Gsellman





Gsellman’s changeup has been murderous, a continuation of last year’s results when it was his best pitch. But he’s got two useful offerings in the fastball and slider, as well, putting him generally above both Wheeler and Matz in terms of pitch effectiveness. Seems like a thing you’d want to take advantage of by using it more often.

It also seems like the sort of thing that would help him against opposite-handed hitters, helping his effectiveness whether he has the platoon advantage or not. So there’s no great reason to manage his appearances by the situation and artificially limit his exposure to lefties, another significant reason some pitchers end up in relief.

Which, to be fair, is part of the reason why Gsellman’s stuff is playing up. His strikeout and swinging strike rates have doubled as he’s being selectively deployed and allowed to lean more heavily into his stuff, so we shouldn’t expect his gains to carry back over. While that’s true, it’s not like he’s added two MPH to his fastball; it’s up only 0.8 MPH over 2017, and all three of his offspeed pitches are up less than 1 MPH over their 2016 figures. A season in which Gsellman rocked a 2.42 ERA and 1.4 WAR in 44 innings.

So he’s been able to sustain this sort of performance as a starter before, and right now his stuff looks a lot more like it did when he was pitching effectively. Hitters are reacting to it very poorly – much like they did then – and the Mets are better for it.

It seems like the bases are covered pretty well here. Messing with a good thing is often a very bad idea, but the Mets aren’t really in a position to be embracing the status quo. Their rotation is more of a weakness than it appears, and the bullpen has a bit more behind it than one would initially think, so taking from one to give to the other likely isn’t disastrous. There’s a lefty-shaped hole and a strong candidate to fill it in Steven Matz, with no worries about diminishing the role of an effective starter because he really isn’t one. And the guy who’s best suited to take his place doesn’t have any obvious red flags when it comes to estimating his performance in the rotation.

At this point, the question moves from why to why not to why hasn’t this happened already?

To which we shake our heads sadly, and say with a catch in the throat: this is the Mets we’re talking about, after all.

2018 Season Preview: New York Mets

This piece is part of the Replacement Level 2018 Team Preview Series. An introduction to the series, as well as a brief explanation of the projections used, can be found here.

2017 Review


Pythag Record

BaseRuns Record

Runs Scored

Runs Against






Could something have gone wrong for the Mets in 2017? Then it probably did. While the team actually slightly outperformed the playoff squad from 2016 on the position-player side, a drop of over 14 WAR from the pitching staff sunk the little brother of New York baseball. Nothing Jacob deGrom could do matztered as the wheelers came off with a rash of harvey-ble injuries, leaving only burnt syndergaarding the remains of the previous season’s top staff.

Offseason in Review:

Key Additions – Jay Bruce, Todd Frazier, Jason Vargas, Anthony Swarzak

The Mets have been easily the most active team in free agency, signing – get this – more than one free agent to deals of multiple seasons! Crazy, right? Apparently enamored with Jay Bruce after his two half-seasons in New York, they snatched him up on a questionable three-year deal. Bruce could easily be worth the $39M, but New York has four 1B/OF incumbents in Michael Conforto, Yoenis Cespedes, Brandon Nimmo, and Dom Smith. While Bruce is a fine insurance plan, the Mets might have been better served targeting another starter. The same could be said of the Vargas signing, as he is coming off 180 well-chewed innings, but doesn’t offer the upside of a Lance Lynn or below-market priced Jake Arrieta. Frazier ended up signing a bargain at two years and $17M, considering he’s been above-average for the last two years and the Mets have to think David Wright is never coming back. Also, Swarzak is fine (Swarzak was super good last year! -editor).

Key Losses – None

The Mets’ top losses after 2017 were likely Jon Niese and Desmond Jennings, neither of whom warrant more words than they’ve already gotten.

2018 Projections







The Mets certainly aren’t a bad team, and they could easily be a good one. If they can get even half-seasons from arms like Noah Syndergaard, Matt Harvey, Steven Matz, or Zack Wheeler, they could reasonably threaten a playoff position. Steps forward among their just-graduating offensive core could make them buyers at the deadline.

Key Players:

More realistically, the Mets will end the season with Jacob deGrom as their WAR leader once again, as he’s led the staff in three of the last four years (finishing 2nd in 2016). If things go horribly, a trade could be on the horizon, but if Noah Syndergaard stays healthy then the Mets have to be considered dangerous. Even more so if Michael Conforto’s breakout season is for real; he could be the offensive linchpin the franchise has lacked since Wright and those times when Cespedes is healthy.

Key Minor League 2018 Impacts:

If we get to stretch the definition of “minor league” a bit, first base prospect Dom Smith is one of the few who might put up an average higher than his ISO. After hitting .330 in AAA and not batting under .300 since A-ball in 2014, Smith faceplanted to a sub-.200 average in his MLB debut. Following every misstep closely was top prospect Amed Rosario, who doesn’t really need to hit given the opportunity for above-average defense at short, but should probably walk more than once per 16 strikeouts. Starter Corey Oswalt threw a career-high 134 dominant innings in his first taste of AA, which means he’ll be starting for the Mets by mid-May and out for the season by the end of June.

Future Outlook:

The Mets are definitely fine. Young outfielders Brandon Nimmo and Conforto would have been handed starting jobs by most other organizations by now, but the Mets. A staff of aces will likely be playing more poker than baseball in 2018, because the Mets. And in an offseason where a franchise that’s hampered by a Ponzi scheme settlement could pick up some half-priced free agents, Bruce and Vargas are the Mets. There is the potential for a good team hanging out in Queens, but it’s too difficult to see them realizing that in more ways than one.