BOSTON -- Buck Showalter knew exactly what Eduardo Rodriguez was capable of.

Fortunately, the Baltimore Orioles' manager didn't have to face his former prospect at his best Thursday in the Orioles' 8-6 win over the Boston Red Sox in the series finale at Fenway Park.

Rodriguez, who was traded last season by Baltimore for Boston left-hander Andrew Miller, was knocked out of the game after a career-low 3 2/3 innings. The 22-year-old left-hander was tagged for six runs on seven hits and struck out five on 67 pitches (43 strikes).

"He's going to be a good pitcher," Showalter said. "He's got a chance to be really solid, and we knew that when we traded him. ... Young pitchers have those moments."

Baltimore (38-34) took two of three in the series and improved to 9-4 against Boston this year.

Matt Wieters' two-run homer highlighted a six-run fourth inning that ultimately did Rodriguez in. The catcher deposited a 2-0 pitch into the Orioles' bullpen in right field with one out in the fourth, giving him three home runs this season.

"I just knew that we needed to do something different to be able to get a win against him than we did the last time," Wieters said, "and we put up a big inning against him."

Rodriguez had faced his former team once before, holding Baltimore scoreless on three hits and three walks while striking out seven over six innings in a no-decision on June 9.

On Thursday, the upstart southpaw looked primed for another shutdown outing against the Birds after he retired the first 10 batters.

"He was dominant," Red Sox manager John Farrell said. "And then he gets in the stretch, they make a little bit of an adjustment, and he's not commanding the baseball as he was when he got into the stretch."

Rodriguez has allowed 15 earned runs in his last 8 1/3 innings at Fenway.

"He was pretty good in his first time around facing those guys," Red Sox shortstop Xander Bogaerts said. "Then obviously they made the adjustments that they needed."

Boston (32-42) fell 10 games under .500 and has lost its last six series against AL East foes.

Left fielder Alejandro De Aza hit a three-run home run against his former team in the fourth to lead the Red Sox bats. Catcher Blake Swihart and shortstop Xander Bogaerts had RBI hits.

Bogaerts also scored on a wild pitch in the seventh, pulling Boston within two runs.

Baltimore starter Miguel Gonzalez (6-4) lasted just long enough to get the win in his return from the disabled list, leaving in the sixth after allowing four runs on eight hits and striking out four in five innings.

Left-hander Zach Britton converted his 17th straight save and 21st overall.

Shortstop J.J. Hardy joined Wieters with a multi-RBI game of his own, doubling and driving in a pair of runs that put the Orioles up 5-1 in the fourth inning.

Third baseman Manny Machado, designated hitter Chris Davis and second baseman Ryan Flaherty each had an RBI in Baltimore's 14-hit attack.

NOTES: Baltimore finished its eight-game road trip at 5-3 and is now 24-20 against AL East opponents in 2015. ... Orioles CF Adam Jones (shoulder) missed his fourth straight game. The center fielder ranks 11th in the American League with a .298 batting average. ... Baltimore starting RHP Miguel Gonzalez had never surrendered more than three earned runs in six career starts at Fenway Park. ... Red Sox INF Dustin Pedroia (hamstring) was placed on the 15-day disabled list and OF Hanley Ramirez (wrist) is day-to-day after both left Wednesday's game with injuries. ... Red Sox RHP Joe Kelly was optioned to Triple-A Pawtucket and C Erik Kratz was designated for assignment. OF Jackie Bradley Jr. and INF Deven Marrero were called up from Pawtucket. Boston also selected RHP Jonathan Aro from Pawtucket. ... Baltimore will host Cleveland for a three-game series and Boston will visit Tampa Bay for three starting Friday.