BOSTON - The Boston Red Sox are hoping an improbable comeback can jump-start their rough start this season.

Rusney Castillo hit a solo homer and an RBI single during a seven-run rally in the eighth inning that sent the Red Sox over the Oakland Athletics 7-4 Sunday for a three-game sweep.

Xander Bogaerts delivered a go-ahead, two-run double. The Red Sox got eight hits in the comeback before ambidextrous Pat Venditte, Oakland's fifth pitcher of the inning, got the last out.

"I think the way in which we won this one has a chance or an opportunity to have as big an impact as the win itself," manager John Farrell said.

Entering the day last in the AL East and five games under .500, the Red Sox provided a glimpse of what type of offence was expected after they spent $183 million on free agents Hanley Ramirez and Pablo Sandoval during the off-season.

"Wow, seven runs in one inning," Bogaerts said. "A lot of people talk about our offence. This is the kind of offence we can be right there."

Boston entered with the third-worst total of runs scored in the AL.

Steven Wright (3-2) pitched 3 1-3 innings of shutout relief for the win. Tommy Layne threw a perfect ninth for his first save.

Kendall Graveman took a shutout into the eighth inning before Castillo led off with a homer. Bogaerts doubled off Tyler Clippard (0-3) and Castillo's single capped the scoring.

The Athletics finished a six-game road trip 3-3 after sweeping the Tigers. It would have been their first winning trip since last June.

"We played great in Detroit," manager Bob Melvin said. "We come in here and lose a couple of tough ones where we're in it up until the last at-bat and then today it looked like certainly early on and deeper into the game we felt like we had a nice win to go home on a 4-2 road trip, but not much you can do about it now."

Graveman blanked Boston on five hits and took a 4-0 lead into the eighth. He was pulled after Castillo's homer.

The Red Sox kept rallying on Ramirez's RBI single and David Ortiz's sacrifice fly. Bogaerts doubled off the Green Monster before Alejandro De Aza and Castillo added RBI singles.

"Any loss is tough especially when you have a four-run lead heading into the eighth, it doesn't make it any easier," Clippard said.

Mark Canha and Josh Reddick each had three hits for Oakland.

Clay Buchholz allowed four runs and 10 hits — five doubles — in 4 2-3 innings.

"That's how good everybody thinks this team is," he said. "It took a while for it to happen."

The Athletics scored three times in the second. Canha had an RBI double, Reddick scored on a wild pitch and Eric Sogard added a run-scoring single.

The A's made it 4-0 in the fourth on Josh Phegley's RBI double before leaving the bases loaded.

Buchholz was coming off a solid stretch of four starts when he posted a 1.47 ERA despite going 1-2.

FINALLY

It was Boston's first series sweep of the season and first three-game winning streak since early April.

NICE EFFORT RUINED

Graveman has a 2-0 record with a 2.55 ERA in four starts since being recalled from Triple-A on May 23. His ERA on the road dropped to 1.98 with the solid outing.

A REAL TABLESETTER

Dustin Pedroia went 2 for 5 and is hitting .394 over 16 games since being moved into the leadoff spot.

TRAINER'S ROOM

Athletics: 3B Brett Lawrie was in the lineup after not starting Saturday to rest his back. On Friday, his broken bat struck a fan, seriously injuring her.

Red Sox: RHP Justin Masterson, on the 15-day DL with shoulder tendinitis, is scheduled to make his third rehab start, Wednesday for Triple-A Pawtucket.

UP NEXT

Athletics: RHP Sonny Gray (7-2, 1.65 ERA) is scheduled to face Texas RHP Nick Martinez (4-2, 2.89) when they open a three-game homestand on Tuesday. Gray currently owns the best ERA in the majors.

Red Sox: LHP Eduardo Rodriguez (2-0, 0.61 ERA) looks to continue his dazzling beginning in the big leagues in his third start when Boston opens a three-game series against his former organization in Baltimore on Tuesday. RHP Miguel Gonzalez (5-4, 3.54) is slated to start for the Orioles.