Mason Miller didn’t leave the mound without a reminder that elite closers are built on fragile bodies. After a strenuous shutout outing for the San Diego Padres against the Seattle Mariners on Friday, he walked out of the training room and apologized to report
SEATTLE — Almost an hour after his most strenuous outing in over a year, Mason Miller stepped out of the training room and apologized to a few waiting reporters.
If not for the presence of fellow reliever Jeremiah Estrada. the San Diego Padres’ hulking closer would have been the last player in the visiting clubhouse.. It was late Friday at T-Mobile Park. where Miller struck out four batters. permitted three base runners and threw 34 pitches in a shutout of the Seattle Mariners.
He’d pitched only once across the past five days. For perhaps the third time this season, he’d looked like something other than just another version of “maybe the most unhittable late-game pitcher of all time.”
“I think it’s just inconsistency, really,” Miller said. “That could be a result of workload. You know, I threw a ton. It was the most innings I’ve ever thrown in a month in April. And I feel great, but sometimes you feel great and there’s some responses too.”
For the Padres, that sentence lands right in the middle of what this season has been about.. San Diego enter Sunday with three of its biggest stars — Manny Machado, Jackson Merrill and Fernando Tatis Jr.. — off to the worst offensive starts of their respective careers.. Tatis, once a feared slugger, is up to 188 plate appearances without a home run.
And yet the Padres are 27-18, coming to life deep into close games. They lead the majors with 39 runs scored in the ninth inning or later, and they rank first, by a wide margin, with a 0.44 ERA in the same time frame.
Miller, of course, is largely responsible for that number. The question the club is racing against is whether what’s working can last.
“We’re trying to make sure that we keep it in perspective that this guy’s really important for us for the season,” said Padres pitching coach and associate manager Ruben Niebla.
Before May, Miller made 15 appearances, two more than his previous high for a calendar month. He also averaged an efficient 14 pitches per inning, overwhelming opposing batters and, amid elevated usage, giving the coaching staff some comfort.
As he has for years. Niebla tracks both numbers and biomechanical markers that indicate when pitchers might be fatiguing or contending with a hidden injury.. Those indicators include velocity, spin metrics, arm slot and overcompensation in a delivery.. The staff builds what Niebla called a more useful picture than pitch-and-inning totals alone.
“It’s more being able to look at science and the data to be able to give you a more holistic approach,” Niebla said. “Obviously, the primary thing is the conversation with the pitcher and how he’s doing, but a lot of times, you also have to trust the medical and the strength (departments).”
That approach matters in part because the Padres’ high-leverage bullpen has largely stayed intact.. Since the beginning of last season. San Diego has mostly avoided significant injury to the relievers that power the strength of the roster.. When Jason Adam suffered a ruptured quad tendon in September — “a fluke injury. ” Niebla said — Adam was tied for sixth in the majors in appearances.
So were Estrada and All-Star left-hander Adrian Morejon.
Adam returned from reparative surgery in April and, despite diminished velocity, has remained effective.. Morejon, despite some poor luck, is throwing harder than ever.. Estrada made a trip to the injured list last month after his velocity plummeted. but since returning he has looked more like his usual self.
“We feel very comfortable with our process right now,” Niebla said.
And last year, Niebla said, those relievers weren’t pushed into vulnerable spots.
“I don’t think that last year any of those guys were put in any vulnerable situation, because they were getting the appropriate days off. … It also gave us an opportunity to really lean on them when we needed to. And we did that.”
Whether Miller’s body responds to the same process will decide whether the Padres can keep doing what they’ve been doing when games tighten.
Time has helped so far. Acquired last summer from the Athletics, Miller has not surrendered an extra-base hit since Aug. 5, his second appearance with the Padres. He has already set the franchise’s record for consecutive scoreless innings, and his Baseball Savant page reflects historic dominance.
But lately, there have been signs that even dominance has seams.
On April 27, a blown call helped the Chicago Cubs scratch across two runs against him. On May 9, he issued two walks for the first time this season. Friday night included a demanding four-out save while throwing his most pitches in a game since September 2024.
“Definitely, you want to preserve him for the whole season,” said Padres manager Craig Stammen, a former reliever himself. “And yet, you want to win a game in the moment, which is difficult to make a decision between those two things when that type of situation is going on.”
Some of it, Miller suggested, could simply be regression toward normal. A heavy workload could also be part of it.
“I mean. we’re playing a ton of close games. so it’s kind of just answering the bell. ” Miller said. adding he sprained his UCL in 2023. prompting the A’s to move him to the bullpen upon his return.. “And I came out of the gates (this season) really strong, commanding the zone, filling it up.. I kind of have gotten away from that recently, which obviously I’m aware of as much as everybody else.. But yeah, just kind of embracing that mentality of just getting your team to the end.”
The staff gave him a break Saturday in the Padres’ 7-4 win against the Mariners.
“It’s really having the open dialogue and then letting him know ahead of time, on a day like today, that he’s down,” Niebla said before the game. “He can take the day and relax and just really focus on recovery.”
With Miller off, San Diego shifted its bullpen plans.. Machado, Merrill and Tatis again went hitless, but the Padres still made damage elsewhere.. Gavin Sheets, Nick Castellanos and Rodolfo Durán all homered for one of the majors’ lightest-slugging teams.. When the Mariners sent the tying run to the on-deck circle in the eighth, Morejon took the mound.. He retired the next three batters before Estrada secured his first save since last July.
For San Diego, it was a demonstration of the kind of depth that makes it possible to protect a single, priceless arm.
Still, the broader math won’t wait. The Padres must score more often to protect their most valuable arm, and Miller’s workload sits at the center of that effort. He is on pace for 77 innings, a dozen more than he’s ever thrown in a season.
“He’s willing to help the team win in any manner he can,” Niebla said.. “There are days that he wants the ball. and we’re trying to make the decision (that) if you are going to take the ball. it’s only going to be for the ninth inning. and that’s it.. There is a lot of days. actually a high percentage of days. where we only have him available for three outs.”
Miller describes the trade-off in similar terms. He said the conversations don’t feel like a rigid script, but like a constantly adjusting game-day reality.
“It’s never like the game plan and situation (is). ‘Hey. we want to use you for four outs today. ’” Miller said.. “It’s just kind of like game situations come. and you don’t really want to get to the end of the game and not have fired me when you have a chance to win the game.. So, I think that’s something we’re all aware of, and the communication has been good.. And obviously, it’s something I’m prepared to do and excited for when I get the opportunity.”
A bullpen can win games quickly. But keeping Mason Miller ready for the season’s hardest weeks might be the part that decides everything.
Mason Miller San Diego Padres Ruben Niebla Craig Stammen Jeremiah Estrada Adrian Morejon Jason Adam T-Mobile Park Seattle Mariners bullpen workload UCL Baseball Savant