This Mariner adds 'great presence' to 'pen

June 9th, 2023

This story was excerpted from Daniel Kramer’s Mariners Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

SAN DIEGO -- It wasn’t just that completely overpowered his former team in his return from the injured list on Tuesday. It was the way he did it.

Muñoz, who missed two months with a right deltoid strain in his pitching shoulder, looked exactly like the high-leverage specialist who emerged as one of the American League’s best strikeout relievers last year. He induced a flyout from Matt Carpenter in an 0-2 count, struck out Ha-Seong Kim looking on a gnarly insider slider and blew a 100.1 mph fastball by Fernando Tatis Jr. to punctuate a hitless eighth inning -- and help secure a much-needed 4-1 win.

“It's a great presence,” Mariners manager Scott Servais said. “Everybody, certainly, in the league respects his stuff. But when he goes out and executes like that, it kind of lifts the rest of the team up a little bit. It's hard to imagine a bullpen guy can do that for a club, but he's done it for us.”

Muñoz won’t be thrust quite back into the role that he held last year right away. Beyond his shoulder issue, Muñoz didn’t have a normal ramp-up in Spring Training after recovering from offseason surgery on his right foot/ankle, and as such, he hasn’t pitched on consecutive days since last postseason, and he did so only 14 times in the regular season.

Ideally, Servais would like to continue installing Muñoz for a clean inning, hoping that such situations would manifest as they did on Tuesday. And it’s not a permanent situation, but rather, the one for now.

“You won't see him back-to-back days here for a little bit,” Servais said. “We’ve got other guys we'll go to in the bullpen if we need to and take it from there.”

Muñoz’s two-month hiatus lasted longer than he or the Mariners envisioned. The shoulder injury was more pesky than painful in the beginning, but it was persistent to the point where he underwent a platelet-rich plasma injection last month and spent the majority of his down time at the club’s Spring Training facility in Arizona.

“The first time that I had pitched, I felt really good,” Muñoz said. “I came back throwing and didn't feel anything. But as soon as I started to get on the mound, I started feeling it in the back of my shoulder again. ... After the PRP was when I started to feel a lot better with the pitch clock.”

As he began throwing again, the delivery on his wipeout slider also felt off. Adjusting to MLB’s new pitch timer had its challenges, too, as it impacted the pace of his mechanics.

“I’ve probably had to slow down my delivery a little bit, because I was too fast to the plate when I started in Spring Training. ... I want to throw faster with my mechanics,” Muñoz said.

Muñoz makes it no secret that he pitches best on adrenaline. A sizable 105 of his plate appearances against opposing hitters last year were in high-leverage compared to 69 in medium and 74 in low.

“As soon as I felt the slider was right was when I felt 100 percent right,” Muñoz said. “Because the fastball was there. A little bit lower in the velocity, but I felt good. I felt that I can put more on it.”

The Mariners bullpen held its own during the 52 games that Muñoz was sidelined, thanks to the emergence of under-the-radar relievers, such as and , and to a lesser extent, , who entered the year on a Major League contract. Seattle’s relievers in Muñoz’s stead had a 3.88 ERA, a 26.8% strikeout rate and a 1.33 WHIP. Paul Sewald has still thrived.

But Muñoz brings another level of firepower, having led all AL relievers with 96 strikeouts last year and really taking off in the second half when he gave up just six runs, zero homers and held hitters to a slash line of .146/.210/.167 (.376 OPS). In five outings in 2023, he’s given up just four hits.

“Sometimes, when guys are that dominant -- and not just in getting three big outs, it's kind of how he gets the outs,” Servais said. “It's over the top. It's great stuff.”