BALTIMORE — The addition of Victor Martinez to the Boston Red Sox lineup has proven to be mutually beneficial to the team and its grateful newcomer.

Martinez had a career-high tying five hits and four RBIs, Josh Reddick and Rocco Baldelli homered, and the Red Sox reached season highs in runs and hits Sunday in a 18-10 rout of the Baltimore Orioles.

Eight different players had multiple hits for the Red Sox, although no one was as productive as Martinez. Obtained from Cleveland on Friday before the non-waiver trade deadline, Martinez singled in a run in the second inning, got two hits in a seven-run fourth, singled in the sixth and added an RBI double in the eighth.

"I'm honored to be on this side now," said Martinez, who now finds himself in the middle of a pennant race. "It's not the same when you're playing and you fall way back in the standings. Just coming over here to a team that is competing every year..."

Martinez joined the team Saturday and was immediately inserted in the No. 3 spot behind Dustin Pedroia and ahead of Kevin Youkilis. After getting an RBI in his debut, the newcomer went wild Sunday.

"Boy, he swung the bat great. Immediate impact," Boston manager Terry Francona said. "I think you're seeing one of the better hitters in the league with some renewed excitement."

It was the fourth straight victory for the Red Sox, whose 23-hit attack included three apiece from Youkilis, Mike Lowell and Dustin Pedroia. Boston led 7-0 in the third inning and 14-6 in the fourth before coasting to the finish.

"The amount of runs and hits they got today speaks for itself in what the problem was," Orioles manager Dave Trembley said. "To say we didn't pitch well would be an understatement."

The Red Sox outscored Baltimore 28-15 in completing their first three-game sweep on the road since June 2-4 in Detroit. Youkilis went 10 for 12 with three walks in the series and reached base 13 straight times (10 hits, three walks) before striking out in the eighth.

Adam Jones and Ty Wigginton homered for the Orioles, now 2-11 against the Red Sox this season.

Boston starter Clay Buchholz gave up seven runs, nine hits and four walks in four-plus innings. He was replaced by Manny Delcarmen (4-2), who allowed two runs in 1 2-3 innings.

Baltimore rookie Jason Berken (1-9) was tagged for six runs and seven hits in 1 1-3 innings. Nine of the 13 batters he faced reached base.

"I think he's stuck and we have to do something to get him out of neutral," Trembley said of Berken, who has lost nine straight decisions.

Boston set the tone in the first inning when J.D. Drew drove in three runs with a two-out double and scored on a single by Lowell. Drew left the game at that point with a tight left groin muscle.

The Red Sox made it 6-0 in the second. Martinez hit an RBI single and Brian Bass walked David Ortiz with the bases loaded to force in a run.

Boston had eight runners in scoring position before Baltimore got its first hit, a second-inning single by Wigginton.

Reddick led off the third with his first major league homer, and the Orioles scored six runs in their half to close to 7-6. Jones doubled in two runs, Aubrey Huff hit a run-scoring double and Wigginton hit a two-run homer off the left-field foul pole.

But any hope of a comeback vanished when Boston used a seven-run fourth to make it 14-6. Lowell started the onslaught with a two-run double, Reddick and Jed Lowrie hit RBI singles, Martinez singled in two runs and Youkilis capped the uprising with a run-scoring single.

Jones hit his 18th homer in the fifth, and Boston added two runs in the sixth, one of them on a bases-loaded walk to Youkilis from Mark Hendrickson.

Nick Markakis hit a two-run double in the sixth for Baltimore, and Brian Roberts doubled in a run in the seventh.

Baldelli, who replaced the injured Drew, homered off Jim Johnson in the ninth.