It felt for a while like Thursday’s Fourth of July matinee was going to be a straightforward affair. Nick Pivetta was dominant, flirting with a no-hitter over seven shutout innings, and the Red Sox seemed to be cruising towards a drama-free shutout win.

Then, the fireworks started.

Despite numerous bullpen collapses and thanks to a game-saving outfield assist by Jarren Duran to help force extras, the Red Sox pulled out a wild 6-5 win in 12 innings to compete a three-game sweep of the Miami Marlins.

David Hamilton and Tyler O’Neill gave Boston the lead for good in the top of the 12th, and Greg Weissert finally put the Marlins away in the bottom of the frame, holding the home team to a sacrifice fly to pull out the chaotic victory.

Along the way Miami twice rallied from two-run deficits to tie the game, but the Red Sox never actually allowed the Marlins to pull in front.

“That was awesome,” O’Neill told NESN’s Jahmai Webster following the game. “We came out swinging the sticks really good the first two games, more of a dogfight today but we stayed in there, stayed grinding and were able to put some runs on the board late in the game, so it was a good one to win.”

But before things got crazy, Pivetta was the star.

Much like Brayan Bello, who spun a gem on Wednesday after a putrid stretch of starts dating back to May, Pivetta entered Thursday coming off a rocky string of outings. Pivetta had failed to get through five innings in three of his last four starts, and he hadn’t struck out more than five batters in any of those despite averaging more than six per game prior.

Whatever the trouble was, Pivetta looked like a completely different guy on Thursday.

The 31-year-old took the mound and immediately went to work carving up the Marlins. Pivetta retired the first nine batters he faced, and after working around a pair of walks in the fourth, went on to send down another nine in a row before Jesús Sanchez recorded his team’s first hit of the game with two outs in the seventh, a triple off the center field wall that Duran had no realistic shot at catching.

Even with a runner 90 feet away and the tying run at the plate, Pivetta came right back and shut the Marlins down, striking out Jake Burger to wrap up his day. He finished with 10 strikeouts, tied for a season-high, while allowing just the one hit and two walks over 89 pitches.

Pivetta’s dominance was needed on a day where the Red Sox had to resort to small ball to generate offense. Boston took a 1-0 lead in the top of the first after Hamilton and O’Neill executed a successful double steal and Hamilton came in to score on a Rafael Devers groundout, and the club added another run on a nearly identical sequence in the seventh.

Otherwise, Miami starter Kyle Tyler was excellent.

Technically a former Red Sox pitcher, Tyler spent less than a day with the organization during spring training of 2022. He was claimed off waivers from the Los Angeles Angels but designated for assignment after playing a single game of catch in Fort Myers, and after that he changed teams numerous other times in quick succession. He eventually landed with Miami, and Thursday he held the Red Sox to two runs on three hits over 5.1 strong innings, by far his best performance in the majors.

It seemed for a while like the two runs would be enough, but Boston’s bullpen couldn’t hold the lead. Justin Slaten allowed a pair of walks with one out in the bottom of the eighth and Brennan Bernardino allowed both men to score on back-to-back RBI singles by Jazz Chisholm Jr. and Bryan de la Cruz, tying the game at 2-2.

Then Kenley Jansen came on in the ninth and allowed a leadoff double to Jesús Sanchez, who appeared to score the game-winning run on a Xavier Edwards walk-off single. But Duran nailed him at the plate, with catcher Reese McGuire smothering Sanchez before his hand got in, and the call stood on replay for the second out.

“That was a great throw, Jarren’s been playing dynamite,” O’Neill said. “A big throw for him right there, that saved the game for us.”

After failing to score in the top of the 10th, the Red Sox found themselves in trouble again when the Marlins got the winning run to third with one out. Zack Kelly escaped the jam, getting two strikeouts to strand men at second and third, but after Boston retook the lead on RBI singles by O’Neill and Enmanuel Valdez, Sanchez struck for a game-tying two-run home run off Kelly to lead off the bottom of the 11th.

But again, the Red Sox had an answer.

Ceddanne Rafaela led off the 12th with a single, and then Hamilton put Boston ahead with an RBI groundout to score the extra-innings ghost runner Romy Gonzalez. O’Neill then came through with what turned out to be the game-winning RBI double, and Weissert came on in the bottom of the inning and limited the Marlins to just a Jonah Bride sacrifice fly to finally close out the win.

“We hung with them and we never stopped playing,” Red Sox manager Alex Cora told reporters.

The Red Sox (47-39) have won four straight and will open a three-game weekend series in the Bronx against the New York Yankees, who are 4-13 in their last 17 games dating back to the clubs’ last meeting at Fenway Park the weekend of June 14-16.