Wednesday, May 29, 2024
AnalysisCincinnati RedsMLBNational LeagueNew York MetsNL Central

Alexis Diaz is Living Up to His Last Name

Edwin Diaz’s reputation as one of baseball’s best relief pitchers is well deserved– he has a 2.84 ERA and 49 saves since 2020. His brother Alexis made his debut this season for the Cincinnati Reds and is pitching at the same level as his brother. This photo has been released into Public Domain.

When Edwin Diaz made his debut in 2016 with Seattle, his rookie season made it clear that he was a force to be reckoned with. He finished 23 of the 49 games he appeared in, finishing with a 2.79 ERA and an even better 2.04 FIP. He allowed very few home runs and his K/9 was an elite 15.3. Diaz garnered Rookie of the Year votes and earned the full time closing job for Seattle, a job he held on to until he was traded to the Mets in 2019. He now closes games for the Mets, who are one of the best teams in baseball. Edwin Diaz is still one of MLB’s premier relievers and is due for a major payday when his rookie contract expires this offseason. When I watch his younger brother, Alexis Diaz, I wonder if history could be repeated.

Am I seeing double?

I will admit that I did not even know who Alexis Diaz was when he made Cincinnati’s roster this season. I assumed he was another roster filler, but I figured he might have some potential, considering he made the Opening Day roster as a rookie. Am I a bad Reds fan for not knowing who he was? Probably not.

Alexis Diaz had virtually no hype going into this season and many (including myself) did not know Edwin Diaz had a brother in the Major Leagues. Kyle Brown of the Cincinnati Enquirer is one of the few people to make this connection prior to the season. Alexis was ranked as Cincinnati’s just 33rd best prospect going into the season by Fangraphs. As a relief prospect, its understandable to be buried in lists because of the unpredictability of the position. However, to be ranked the 9th best relief prospect in an organization? No wonder he went so under the radar. His Fangraphs scouting report stated that “[he] will likely be in the bullpen most of the year, and projects as a middle-inning reliever.” Not necessarily glowing words from Eric Longenhagen and Tess Taruskin. The blurb noticeably omits his relation to his brother Edwin, further showing how unknown Alexis was.

Diaz had a stellar April, only allowing one run in 9 innings pitched. He pitched exceptionally well in May too– and one particular game garnered the attention of baseball fans everywhere. On May 17th, Alexis struck out Cleveland Guardians star Jose Ramirez to record his first major league save in exciting fashion–a landmark game in his debut season to lower his ERA to 0.52. This performance became even more shocking when the baseball world realized Edwin Diaz recorded a save earlier in the day! According to, this was only the third time a pair of brothers recorded a save on the same day.

Alexis Diaz has assumed the role of the first option in Cincinnati’s bullpen because his season stats have been so incredible. The only time he has allowed more than one run in an appearance was last Saturday when he surrendered a 3-run homer to Juan Soto. I’m not making excuses for Diaz, but if your only stain on the season is because of Juan Soto, you’re a pretty good pitcher. Diaz has a 2.16 ERA on the season with a 3.42 FIP (these numbers become 1.13 and 2.93 respectively if you ignore the Soto outlier) and his underlying statistics support continued success. Diaz relies on two pitches– an elite fastball and a whiff-inducing slider.

His fastball spins to a rate of 2692 revolutions per minute, good enough for *checks notes* 100th percentile among MLB pitchers. Batters barely touch the pitch (.107 batting average against, 32.9% whiff%) which he lights up the top of the strikezone with. He throws the pitch just a hair above average velocity wise, so he relies on elite location and spin rates. Spincinnati is back.

Courtesy of Baseball Savant

The slider performs exceptionally well, too. He compliments the high fastball with the breaking pitch down low, often thrown for strikes. It has a 24.1 putaway percentage and a staggering 42.6% whiff percentage. Simply put, with a 95th percentile whiff percentage, both of Diaz’s pitches miss bats.

Diaz’s exit velocity allowed is a bit more modest (just 64th percentile with a 87.9 EVA in 55 BBE) but still well above average. Expected statistics like xBA, xSLG, xwOBA, and xERA are kind to Diaz and don’t suggest regression. Diaz’s sole weak point appears to be issuing free bases as he sports a 12.7% BB%. We have seen this become an issue already– in 3 of the 4 games in which he surrendered a run he walked a batter. Diaz has been able to minimize the walking problem by not allowing hits. When Diaz issues a walk they usually don’t score because he misses bats. This is a perfectly viable strategy and one many relief pitchers utilize, but it is extraordinarily risky. If Diaz sees any regression in his stuff, expect his ERA to balloon. When hitters do make contact, they hit flyballs at a concerning rate. Considering Diaz plays for the Reds, a team which plays half of their games at a park deservingly nicknamed “Great American Small-Park” a 38.2% flyball rate induces stress. 5 of his 6 earned runs have been at GABP, his home park. Alas, throwing high fastballs gives as well as takes.

The good thing about Alexis Diaz is that there aren’t any indicators for his stuff to regress. His spin rates were always good and he has proven his game against some of the best hitters in baseball. I expect Diaz to maintain his statistics at the elite level they currently reside as he continues to indeed live up to the Diaz name.