The Red Sox took the lead on a passed ball in the 10th inning and lost it on a wild pitch in the same inning.
It took them until the 11th to finally solve it, and when they did, it was the man who had been 0-for-4 with two strikeouts on the night who ended it.
Jarren Duran stepped in against Miami lefty Cade Gibson with the bases loaded and one out in the 11th, Willson Contreras on first, Jahmai Jones on second after a walk, and Wilyer Abreu on third after an out scored him.
Duran took an 80.4 mph sweeper and drove it 412 feet to right-center field at 105 mph off the bat. Grand slam. Boston 7, Miami 3. Fifth win in a row. Ninth in their last 12 games.
"We have to win," Duran said afterward. "There is no other option. That is the identity that we have created."
He is having a down year by his own standards, a .209 average and .636 OPS, well below the .256 and .774 OPS he put up last season. But his 17 RBIs in the ninth inning or later lead all of Major League Baseball.
He knows how to be there when it counts. Mickey Gasper had a two-homer game and rookie Payton Tolle carried a no-hitter into the fifth for the Red Sox, who are 73-59 and making a serious push in the AL Wild Card race heading into September.