OAKLAND -- The Red Sox are running out of ways to describe Nick Pivetta's transformation since he joined the team's relief corps. For his latest feat, the right-hander just did something that only five other pitchers in the Modern Era have accomplished.

Pivetta set a franchise record for the most strikeouts by a reliever, punching out 13 batters across six innings in a 7-0 Red Sox win over the A's Monday night at the Coliseum. He became the sixth pitcher in AL/NL history to strike out 13 or more in relief, joining an exclusive club:

• Randy Johnson: 16 strikeouts in seven innings on July 18, 2001
• Walter Johnson: 15 strikeouts in 11 1/3 innings on July 25, 1913
• Rube Marquard: 14 strikeouts in eight innings on May 13, 1911
• Denny McLain: 14 strikeouts in 6 2/3 innings on June 15, 1965
• Billy O'Dell: 13 strikeouts in nine innings on July 4, 1961

Of those six members, Pivetta is the only one who did not allow a hit. Since he faced 20 batters on Monday, Pivetta's strikeout rate (65%) among the six is second only to Randy Johnson, who whiffed 16 of the 23 hitters he faced (69.6%).

Pitching for the D-backs against the Padres, Johnson set the record with 16 K’s in relief after entering to begin the third inning of a game that had been suspended the previous day due to a power outage caused by a transformer explosion at San Diego’s Qualcomm Stadium.

After a dicey beginning to his 2023 campaign, Pivetta has seen an astounding resurgence since he was shifted to the bullpen in mid-May.

"A lot of people were worried when he got 'demoted' to the bullpen because he wants to be a starter, and he has the potential to become a starter," manager Alex Cora said. "But he took it the other way. He's like, 'You know what, I'm going to contribute. I'm going to help this team. … Whatever role you give me, I'm going to go out there and perform.'"

Pivetta maintained that his mentality does not change whether he's starting or entering in relief.

"I just go out there and I execute what I need to execute," Pivetta said. "Just get ahead of guys, compete in the zone, use my stuff in the zone and then expand the zone after that."

Along with opener Brennan Bernardino and Chris Martin, Pivetta led the way as the Red Sox shut out the A's on just one hit. The trio of Boston arms combined for 18 strikeouts, the A's most in a game this season.

There's no doubt about it -- though it was a team effort backed by production at the plate, Pivetta's performance stole the show.

"I think you can just feel it, the way the ball comes out of his hand," said backstop Connor Wong, who went 3-for-4 with three RBIs. "When I'm catching it, I can feel it, how explosive it is."

Pivetta entered the game in the third and struck out the side in three innings -- the fourth, sixth and seventh -- the latter two times as part of a stretch in which he punched out seven consecutive batters. It's not the first time the 30-year-old has dominated the A's on their home turf -- he has yet to allow a run in 20 innings (three appearances) at the Coliseum -- but he took it to another level on Monday.

“That’s the best I’ve seen him," A's manager Mark Kotsay said. "You run into a buzzsaw sometimes. Tonight seemed to be that night.”

Following the dominant performance, Cora reiterated a point that he had made prior to the game: Pivetta's days pitching in relief are likely numbered.

"We were joking on the bench … maybe he feels now that he should become a starter. It's the other way around: the better he pitches, this is a structure we need," Cora cracked. "No, no. But like I said, at one point, probably, he needs to start."

The Red Sox have been rolling with three healthy starters -- Brayan Bello, James Paxton and Kutter Crawford -- and that structure has worked with the requisite number of off-days. But Cora is wary of stretching his relievers thin with too many bullpen games when Boston's schedule becomes more demanding, and Pivetta is the logical choice to join the rotation if Garrett Whitlock, Tanner Houck and Chris Sale are not healthy by that point.

For his part, Pivetta is confident that his momentum of late can carry over to any role he appears in.

"I don't really know what it is," Pivetta said. "I'm just doing what I've always been doing. … Doesn't matter where I'm pitching or when I'm pitching. Being consistent is the most important thing for me, and that's just what I focus on."