BOSTON -- Right-hander Bryan Shaw has made 733 appearances over the course of his 12-year career. The first 732 of those outings were in relief, until Tuesday night.

In the second matchup of a four-game set at Fenway Park, Shaw made his first big league start in an 8-3 win over the Red Sox. The 34-year-old went a season-high 2 1/3 innings, giving up two runs on three hits with one walk and two strikeouts -- and set an American League/National League record in the process.

• Box score

Shaw's 732 career appearances entering Tuesday marked the most games pitched prior to a player making his first career start in AL/NL history (since 1901), according to the Elias Sports Bureau. David Robertson held the previous high with 670 relief outings before making his first start in 2021 with the Rays vs. the Marlins.

“I figured it was probably close,” Shaw said of setting the record. “Usually you don’t go there [to the rotation], usually it’s the starters moving to the ’pen, not the other way around. I figured it was something close to that. But no, that’s cool, I’ll take it. I’ll take any records I can get.”

One night after putting up just one run in the series opener, the Guardians backed Shaw with a solo home run from Austin Hedges in the second and a third-inning three-run blast courtesy of Nolan Jones. Cleveland recorded five more hits than Boston (12-7), with three players (Steven Kwan, Amed Rosario and Josh Naylor) recording a multihit game.

After Nick Sandlin took over for Shaw and escaped a jam in the third, lefty Kirk McCarty came in to pitch four scoreless innings. McCarty entered the game after a roller coaster of a month, which saw him: designated for assignment by the Guardians on July 3, claimed off waivers by the Orioles on July 6, designated for assignment by Baltimore on July 12 and then claimed off waivers by Cleveland on July 14. His one-hit, one-walk and four-strikeout performance on Tuesday marked a hopeful turn for the lefty, in addition to earning McCarty his first career win.

“It's special,” McCarty said. “The past month has been really hectic for me and my family, and they've stuck with me through it and continue to support me through it. And it's really special, tonight’s real special.”

Cleveland turned to its bullpen on Tuesday with No. 4 starter Aaron Civale sidelined with right wrist inflammation. Manager Terry Francona said that Civale, who was removed from his start against the White Sox on July 13 after throwing just 20 pitches in the first inning, is throwing from around 130 feet, and the Guardians hope to know more about his timetable once he starts throwing off a mound.

The Guardians’ rotation has been tested in 2022 with an MLB-high nine doubleheaders this season. The good news? After coming out of the All-Star break with a twin bill against the White Sox on Saturday, the Guardians have just two scheduled doubleheaders left: Aug. 15 vs. Detroit and Sept. 17 vs. Minnesota.

Despite battling some less-than-ideal scenarios, Cleveland’s rotation has stayed afloat with a 4.03 ERA entering Tuesday (eighth lowest in the AL) and a 1.26 WHIP (sixth best in AL). Triston McKenzie’s 3.03 ERA ranks 10th best among qualified starters in the AL, with Cal Quantrill 18th best with a 3.75 ERA.

With Quantrill, McKenzie, Shane Bieber and Zach Plesac set to make their scheduled starts over the next four days, Sunday remains the only day in question with Civale out. Francona didn’t specify whether the Guardians will use another bullpen game or call somebody up, but Shaw made it clear he’s ready to go if needed.

“I mean, I'm penciling it. I don't know what they're doing,” Shaw said while laughing.