How Reds' Alexis Díaz went from longtime minor-leaguer to elite MLB closer overnight

CINCINNATI — It’s hard to believe this when you watch him now, but Alexis Díaz didn’t record his first professional save until just two years ago. 

Leading MLB in saves with 34, the 26-year-old right-hander has emerged this season as one of the best relievers in the sport. While his dazzling 2022 rookie campaign might have gone under the radar on a 100-loss Reds team, his evolution into one of baseball’s most vicious game-enders has been a massive part of Cincinnati’s surge out of the basement of the NL Central and into the thick of the NL playoff race. 

Díaz's status as one of the game’s best closers is no longer in question. He was the lone Reds representative at the All-Star Game in Seattle and looks like a foundational piece in Cincinnati for years to come. What makes his trajectory so unusual is how he simultaneously was known by many — thanks to his big-league brother — while also flying completely under the radar until he was blowing fastballs by the best hitters in the world as a rookie.

Díaz did not enter pro ball with nearly as much hype as his older brother. Edwin Díaz was a third-round pick by Seattle in 2012 as part of a historically great Puerto Rican high school class that also featured Carlos Correa and José Berríos. 

Perfect Game did rank Alexis Díaz as the No. 1 player in Puerto Rico in 2015, but he was not considered one of the best prep arms available like his brother. The Reds selected him in the 12th round and gave him a $130,000 signing bonus. 

Tommy John surgery in May 2016 — just a few weeks before Edwin made his MLB debut — took Alexis off the radar at a very early stage of his career. After throwing well as a starter (3.02 ERA; 67 strikeouts in 53.2 IP) in rookie ball in 2018, Díaz finally made his full-season debut in 2019 as a 22-year-old and pitched mostly out of the bullpen. The strikeouts continued to pile up (77 in 59 innings), but the command and run production were shoddy. 

Entering what would eventually be a canceled minor-league season in 2020, Díaz’s prospect stock was wavering at best. By the time he reported to spring training in 2021, he was a 24-year-old who had yet to pitch above A-ball. 

With his days as a starter officially behind him, Díaz opened the 2021 season in Double-A as part of a Chattanooga pitching staff that also featured many of the talented hurlers he shares a clubhouse with today, including Hunter Greene, Nick Lodolo and Graham Ashcraft. He was also in the same league where his brother had transitioned to the bullpen full time back in 2016; a move that rocketed Edwin to the big leagues by early June. 

Alexis' Southern League stop didn’t catapult him to the majors quite as quickly, but it sure played a significant role. A little less than five years after Edwin had recorded his first professional save — fittingly, against Chattanooga — Alexis entered the second game of the Lookouts’ season with two outs in the final frame after a teammate allowed a couple of runs and loaded the bases. 

"Things got a little bit interesting in that last inning," Díaz recalled through interpreter Jorge Merlos. "And sure enough, they brought me in. I was super excited to come in and be able to get the out at the end." 

He got a called third strike to finish it. S: Díaz, A (1)

It was the first of many.

Díaz would actually only record one more save that season with the Lookouts, but his 70 strikeouts in 42.1 innings raised his prospect stock considerably. The command was shaky, but the flashes of brilliance made the occasional high-stress outing well worth it. 

"I remember every time he would come in, it was like, 50/50 — you didn't know if you were gonna get strikes or if you were gonna get what you see right now," Lodolo said. "He always had great stuff. When he was on, you're like, ‘holy s---.’"

Without having ever pitched in Triple-A, Díaz earned a spot in the bullpen out of spring training in 2022 and went on to author one of the more dominant rookie relief seasons we’ve seen this century, posting a 1.84 ERA in 63.2 innings with a .129 batting average against that ranked second-lowest among all qualified relievers — even ahead of his brother. 

Though the expectations for the Reds remained timid at best, Díaz entered 2023 as one of the more exciting young closers to watch across the league. But before Opening Day arrived, the tone of his season slightly shifted when his brother, who'd established himself as the best closer in baseball with the Mets, suffered a serious knee injury while celebrating Puerto Rico’s victory over the Dominican Republic in the World Baseball Classic. 

While Edwin has spent all season rehabbing, Alexis’ profile has continued to rise. Off the field, the two remain in touch as often as ever. 

"Our relationship has been the same, whether he was injured or not," Alexis said. 

Edwin hasn’t had his own games to worry about, but even when he did, he’d be keeping up with his younger brother's results. 

"We're always checking on each other," Alexis said. "He's always checking on me. If he's at an early game and I'm playing later, he's going on his iPad and checking out how I'm doing. It's been just constant communication."

From a distance, Edwin has watched as Alexis has evolved into an even better version of his impressive rookie self. 

While any individual save situation has high stakes, the bigger picture lacked any significant pressure during Alexis Díaz’s rookie year. By the time Díaz recorded his first big-league save on May 17, 2022, the Reds were 10-26, having endured a historically horrific 3-22 start that immediately threw last season off course.

Now, sparked in large part by a new wave of talented rookies, the Reds have been one of the biggest surprises of the 2023 regular season, and remain within striking distance of Milwaukee atop the NL Central. Suddenly, Díaz’s job means a lot more than just finishing games for a last-place team — and he’s thriving. 

"He’s a stud," rookie infielder Matt McLain said. "I know he wants to do it every day, I know he can’t, but I can feel that he wants to every single day. And he’s not afraid to face anyone, and he wants to face the best." 

Though it was always going to be hard to drastically improve on his statistical dominance from a year ago, Díaz made one major change this year to help elevate his game: an increased reliance on a slider that he never felt was at its best in 2022. 

"Last year, I didn't have my slider. I just couldn't find it, I couldn't control it as well," Díaz said. "This offseason, I worked on it really hard. I knew that I had to get it together and make sure that I was able to work with the fastball and slider and sure enough they've been able to really work compatibly well."

Last year, Díaz’s 1-2 punch featured a roughly 65/35 split in favor of his heater. This year, it’s almost dead even, with Díaz having thrown 442 fastballs compared to 458 sliders. That even distribution has made stepping into the box all the more uncomfortable and unpredictable for opposing batters; a coin flip from hell, in a sense. 

While Díaz’s pitch mix has been tweaked a bit in his sophomore campaign, one element of his profile that has remained a constant is what might be his biggest pitching superpower: unparalleled release extension. Extension is how far down the mound a pitcher gets when he releases the ball, and it impacts the perceived velocity on a pitch, since it affects how close a pitch is being delivered to home plate and lessens the amount of time a batter has to react. In other words, 95 mph released with significant extension can look just as fast as 98 mph without it. 

Díaz combines elite extension — 7.7 feet on average, tops in MLB and even up a tick from the 7.5-foot mark he averaged in 2022 — with a lower release height that creates a unique and very challenging angles for opposing hitters to deal with, as seen in the chart below (via Baseball Savant).

"He feels like he's throwing closer," Reds catcher Luke Maile said. "The fact that he's the last guy that you get to see of the day, it feels like somebody scooted the mound up."

Díaz might not have quite the raw velocity of his older brother — his fastball averages 94.6 mph, which is on par with the average reliever across MLB — but its unusual release point and elite spin rate allow his heater to be similarly effective. 

"I always said he has a better fastball than his brother," declared fellow reliever Fernando Cruz, who has known both Díaz brothers for years and was teammates with both of them on Team Puerto Rico in the World Baseball Classic. "But, obviously, [Edwin] is throwing 103.

"But I stick with [Alexis]’s fastball. I think it’s unhittable, and he knows that, and he has confidence in it. That's what makes him impressive."

The walks — though down from 12.9% last year to 10.9% this season — remain a bit high for any manager’s liking, but Díaz has been so consistent at working his way out of self-inflicted jams that his high-stress innings almost always have a happy ending. 

"You have to be really good to be able to pitch out of situations like that," manager David Bell said of Díaz earlier this year. "It just speaks to how good he is and at a very early age how much confidence he pitches with."

It’s that confidence that the team quickly identified and rallied around as his rookie year progressed in 2022 and into this season as the Reds have started to stack wins. 

"It happened really early on," Bell said. "He showed it last year, but he continues to get better."

"Sometimes, it's easy to forget that he's still really early on in his career because it looks like he's been doing it for 20 [years]," Maile said. "Obviously, his fastball and his slider are right up there among the best in baseball. But I think just his presence alone is something that stands out the most."

Cruz added: "His talent is on another level, but his attitude is even better. His attitude of competition and his attitude of, ‘I gotta produce at higher levels but I have to be calm at the same time’. That's something that stands out."

Having seen him in his shakier form in the minors, Lodolo now marvels at how automatic his teammate has become. 

"Now, it's like, whenever he goes out there like you expect a zero. It's almost unfair to expect him to [do that]," Lodolo said. "But now every time he goes out there, it feels like, ‘Oh, we won.’"

The fickle nature of closer and reliever success might make such expectations of perfection unreasonable, but Díaz embraces them and has the confidence to match. He relishes each and every opportunity he gets to enter the game in the ninth inning with a lead. His favorite part?

"It's just about closing the door on the game," Díaz explained. "I come in with all this energy, just to close the door, and I know that I'm going to do it.

"It's just really exciting to go out there and do that." 

Those feelings of joy and confidence are shared by his teammates, both in Cincinnati and elsewhere

"I've been working with him since 2019," said Cruz, who's played with Díaz in the Puerto Rican Winter League. "He's come a long, long way. I knew he was gonna be special, and I'm so happy to be a part of and be witness to it.

"The greatness has been building in the last two years."

Jordan Shusterman is half of @CespedesBBQ and a baseball writer for FOX Sports. He has covered baseball for his entire adult life, most notably for MLB.com, DAZN and The Ringer. He's a Mariners fan living in the Eastern Time Zone, which means he loves a good 10 p.m. first pitch. You can follow him on Twitter @j_shusterman_.