SEATTLE -- As Luis Castillo came set for what he thought would be his final pitch of the night, he had his trademark fist clench ready to roll.
He was on the cusp of clearing his seventh scoreless inning, had flashed plus-plus stuff all night and was seeking his season-high eighth strikeout when Pirates slugger Oneil Cruz stepped to the plate. But the gesture that’s been synonymous with “La Piedra” was put on hold after he threw two balls, thus creating more palpable tension for both the packed house and the pitcher on the mound.
"If you notice it, you can kind of tell in my mechanics,” Castillo said through an interpreter. “I was ready to throw that fist up. But we didn't get him in those first two pitches. And then all I had to do was throw the fastball toward him and we were able to get him and we were to celebrate with that fist pump.”
Indeed, Castillo dialed up his 99th and final pitch of the night to 96.8 mph, froze Cruz on an offering that clipped the outer black, thrust his pitching arm with his hand clenched and sent Seattle on its way to a 1-0 win over the Pirates at T-Mobile Park on Saturday night.
"Tonight, wow,” Mariners manager Dan Wilson said. “That was exceptional.”
The fist pump is a gesture that Castillo has used regularly throughout his career, but more sparingly in 2025. An easy correlation is that his strikeouts are down -- his 20.2% K rate is a drop from 24.3% last year and 27.3% in 2023, when he was a third-time All-Star -- but it’s also more deliberate than that.
"I think it depends on the situation,” Castillo said. “Sometimes when you get runners in scoring position, and then you're able to strike out that last batter, you bust out the celebration. Also, when I know that I'm around 90 or close to 100 pitches, and you're able to get that last strikeout to probably end the outing, that's when I bust it out.”
Castillo also revealed that he’s much more thoughtful about when to unveil it than it might seem.
"Of course, of course,” Castillo said. “I know the situation with two strikes. Here comes my perfect pitch, and I'm going to celebrate with the fist pump. ... It took us a little longer, but we were able to celebrate.”
Saturday’s punctuating moment was the most defining one in a night in which Castillo was dynamite and turned in easily his best start of 2025. He dialed up both his fastballs to the levels he showed when at his absolute peak while limiting the Pirates to just two baserunners, both via singles, to go with zero walks.
And for a Mariners rotation that’s weathered more ups and downs this season than most anticipated, his efforts -- on the heels of six scoreless innings from All-Star hopeful Bryan Woo the day prior -- offered promise for what the group is banking on will be a strong second half.
"I think this team is going in the right direction,” Castillo said.
Castillo leaned heavily on his heaters on Saturday, seeing a full 1 mph uptick in velocity on his sinker (to a 96 mph average) and a 0.6 mph spike on his four-seamer (95.7 mph average), pitches he utilized for seven of his eight punchouts. Though the fastballs were the jugular pitch, Castillo also had an improved slider that was actually just as effective for swing-and-miss, with six whiffs on the 10 swings he generated.
"As the season is progressing, I think I'm progressing pretty well, and I'm feeling pretty well,” Castillo said. “And I think that's why we're at the point of season where I think I can kind of locate my pitches where I want them at the velocity that I want.”
For the season, Castillo now carries a 3.31 ERA in 18 starts, which ranks 27th among 70 qualified starters and trails only Woo’s 2.77 ERA for the team lead. And his 103 1/3 innings (just under six innings per start) are the 22nd most in MLB.
He might not have the same stuff from his seasons of absolute dominance, but when Castillo is on -- like he was on Saturday -- he’s still a reliable workhorse.