Ivy League Cubs

By: Jake Russell

It seems as if the reliever market is really heating up now, as the Mets have made two moves to beef up their bullpen over the span of an hour.

In 2023, the Mets bullpen was 7th worst in terms of fastball velocity, and this continues a trend of David Stearns adding guys with very good velocity during the offseason. (Of course, getting Edwin Díaz back is helpful, as well). 

Fujinami averaged 98.4 MPH on his fastball last season, though he did begin the season as a starting pitcher before being moved to the bullpen. The surface stats of Fujinami aren’t pretty: as a reliever, he allowed an ERA of 5.14 and walked 12.5% of batters. However, he did strike out 26.2% of his opponents from the bullpen, and the upside here is pretty easy to see. He averaged 115 Stuff+ last season according to Eno Sarris and Max Bay’s model. He also gets a monster 6.9 feet of release extension off the mound from a relatively lower arm slot, though he gets a lot of run on his four-seam and just 14 inches of Induced Vertical Break. Still: it’s a plus pitch that grades out well and generates whiffs 25% of the time.

Beyond that, he also uses a hard, devastating splitter, and occasionally a cutter and sweeper. The splitter is easily his best pitch, and he picked up a 37.2 whiff% with the splitter last season. Though obviously splitters are hard to command, at 93 MPH it’s a plus-plus pitch and I am surprised he doesn’t throw it more.

The command is clearly his biggest issue, as he had a 4th percentile chase% and 6th percentile walk% despite an above average zone% last season. I don’t think it helps that he threw his fastball 57% of the time. While it’s a solid pitch, I don’t think it’s nearly good enough to be doing that. Perhaps the Mets will attempt to diversify his sequencing and get him to throw more next season. Would not be surprising at all if he were able to take a leap.

Diekman is another interesting pickup for the Mets. He was released by the White Sox after a painful start with them, only to sign with the Rays. He finished his season with the Rays at a 2.18 ERA and a 28.6 K%.

Similarly to Fujinami, the stuff is there for Diekman, but command has always been an issue. Diekman’s four-seam fastball is pretty good, though to be fair it plays more like a two-seamer. It has just 11 inches of Induced Vertical Break, but runs 17.4 inches armside! There’s more than one way to be effective, and Diekman is certainly an example of that. His sweeper sweeps 12 inches gloveside, and though it’s a good pitch, that is a LOT of horizontal separation between his fastball and sweeper. Perhaps, that is partially the cause of his 4th percentile chase% and 1st percentile walk%. It may be too easy for hitters to discern between pitches. But, he has been a very effective reliever in his career.

I also should add that he has a changeup that he throws exclusively to RHB. (He actually hasn’t thrown one to a lefty since 2016). He has tended to be pretty effective against righties, but using that changeup against Opposite-handedness is a pretty good move. It also has 16 inches of arm-side movement and a good bit of carry.

Diekman is certainly much more of a “sure thing”, so to speak, than Fujinami, but it would not be shocking if Fujinami had a very good 2024. I like both of these additions, and the Mets’ bullpen plan is clear: get guys with really good stuff and hopefully they get strikeouts.

Picture credit: Kiyoshi Mio, USA Today Sports