BOSTON -- David Ortiz hit a grand slam for one of the Red Sox's four homers as they set a season high in runs, beating the Miami Marlins 15-5 Wednesday night on the hottest day of the year in Boston.
Mike Aviles, Jarrod Saltala macchia and Will Middle brooks also homered one night after Ortiz hit one of Boston's three homers in a 7-5 victory over Miami.
With a game-time temperature of 95 degrees, the Red Sox pounded out 16 hits and won their fourth straight game and sixth in their last seven. They moved out of last place in the AL East at 35-33, passing Toronto after the Blue Jays lost 8-3 to Milwaukee.
The Marlins lost for the 12th time in 14 games despite scoring four runs and nine hits in six innings against Felix Doubront (8-3).
Florida's Ricky Nolasco (6-6) gave up nine runs and nine hits in 31 3 innings.
The Red Sox offense has come alive in the past week with at least seven runs in four of their last six games.
On Wednesday, Aviles's three-run homer gave Boston a 3-2 lead in the second. In the third, Cody Ross' three-run double, on which Ortiz hustled home where the throw hit him and bounced away from catcher John Buck, made it 6-2.
Then Ortiz's 11th career grand slam, and 18th homer of the year, highlighted a six-run fourth that put Boston on top 12-4. Daniel Nava was on base at the time with one of his four singles.
Before the game, Miami manager Ozzie Guillen said he wouldn't change his lineup to help stop the slide.
Buck hit his fifth homer, a solo shot that made it 13-5 in the seventh, but immediately clutched his right hamstring and trotted slowly around the bases. He remained in the game before leaving for a pinch hitter in the ninth.
For the second straight game, the Marlins led 2-0. They scored in the first on singles by Jose Reyes and Hanley Ramirez and a double-play grounder by Giancarlo Stanton. They added a run in the second on a double by Justin Ruggiano, a single by Omar Infante and a groundout by Gaby Sanchez.
But the Red Sox quickly jumped ahead by four runs after three innings.
Then the Marlins cut the lead to 6-4 in the fourth on a solo homer by Logan Morrison, who drove in all five runs on Tuesday, and a run-scoring groundout by Sanchez.
Boston drove Nolasco from the game in the fourth when singles by Aviles, Nava and Ryan Kalish produced one run. After a single by Adrian Gonzalez loaded the bases, Ortiz homered for the third straight game, a grand slam off Chris Hatcher. Saltalamacchia's 13th homer finished the inning.
Nick Punto scored the Red Sox 13th run on Hatcher's wild pitch in the fifth and Middlebrooks hit his seventh homer, a two-run shot in the eighth.
NOTES: Boston 2B Dustin Pedroia missed the game as a precaution after feeling discomfort in his right hand on his last at bat in Tuesday night's win. ... Nolasco lost his third consecutive start and fourth in his last five. ... In Thursday night's series finale, Carlos Zambrano (4-5) is set to pitch for Miami against Daisuke Matsuzaka (0-2). ... The Red Sox signed SS Deven Marrero, their first-round pick and 24th overall in the amateur draft. He hit .325 in three seasons at Arizona State. He will be assigned to Single-A Lowell. ... Nava's four hits matched a career high set on June 1. ... Ortiz tied Joe Carter for 52nd place with 396 homers.