When the Mets acquired Edwin Diaz along with Robinson Cano from the Seattle Mariners in December 2018, there were a lot of fans that were frustrated with the package of prospects sent to Seattle, but at the same time excited about the potential Diaz brought to the back-end of the Mets bullpen.
He had an incredible 2018 season in Seattle, when he led the league with 57 saves while also posting a 1.96 ERA, 1.61 FIP, and 15.2 K/9.
Mets fans hadn’t seen a reliever with this kind of stuff since Jeurys Familia was making opposing hitters look silly with his 95 MPH splitter back in 2015-2016.
Diaz’s first season in Flushing obviously didn’t go as planned, with the then 25-year-old blowing big spot after big spot, finishing the year with a 7.23 ERA and 15 HR allowed over 51 appearances in the 9th inning.
And after another rough start in 2020, it seems like Diaz is slowly getting back to that pitcher we all loved watching highlights of in a Mariners uniform.
The Puerto Rico native is currently ranked in the Top-5 among National League relievers in FIP (1.86), K/9 (19.2), K-BB% (38.2), and FangraphsWAR (0.8).
A lot of those numbers likely have to do with the fact that Diaz was demoted to low-leverage situations for a good portion of the season, but it also has plenty to do with him rediscovering that electric slider.
In 2018 with Seattle, Diaz threw the slider 436 times, and had an incredible 54.0 whiff percentage and .234 slugging percentage.
He was still getting a lot of swing and miss on that pitch in 2019 (43.2 whiff percentage), but the .622 slugging percentage shows that it just wasn’t the same.
But in 2020? This might be the best it’s ever been for Diaz.
He has thrown the slider 153 times thus far in his 21 appearances, and it’s produced a 62.2 whiff percentage, .171 slugging percentage, and an average exit velocity of 81.6 MPH — all career-highs for the 26-year-old.
The 4-seam fastball, however, still isn’t where Diaz wants it to be. A .273 batting average and and .485 slugging percentage are both career lows.
So he will need to get that pitch back to where it was 2-3 years ago if he truly wants to be that elite closer again in New York City.
Just because Diaz looks good now, does that mean we have seen him blow his last game in a Mets uniform?
Most likely not, due to the natural volatility of relievers, and a much more steady diet of high-leverage situations coming his way with Seth Lugo locked into the starting rotation.
But if he can continue putting hitters away with that slider and work on his fastball command a bit more, I’ll bet that we’ll all be doing a lot more cheering than booing of Diaz’s name in the Citi Field stands for years to come.
