Daniel Mengden pitched six strong innings after the delay for the A's, who won a second in two days at Boston to clinch their second straight series win over the Red Sox.

Oakland wasted no time jumping on Red Sox starter Eduardo Rodriguez, with Marcus Semien and Chad Pinder opening the first with singles.

Two outs later, Chapman smacked his double to right field, chasing Semien and Pinder home and giving Mengden an early 2-0 lead.

Stephen Piscotty, batting for the first time since missing four games while on the bereavement list due to his mother's death, made it 3-0 in the second inning with his third home run of the season.

The Red Sox chipped away at the Oakland lead, scoring once apiece in the fourth and fifth innings. Andrew Benintendi's solo homer, his third of the season, got Boston within one in the fifth.

Canha then gave the Oakland bullpen some breathing room with his two-run double, which came with two outs in the eighth after Khris Davis and Chapman had singled.

Mengden (3-4) got the win, allowing two runs (one earned) and eight hits in six innings. He struck out three and did not walk a batter.

Lou Trivino retained Oakland's 3-2 lead in the seventh and eighth innings, limiting the Red Sox to one hit and one walk.

Blake Treinen then survived a shaky ninth inning for his eighth save of the season.

Treinen struck out Rafael Devers to open the inning, but the third strike got past A's catcher Jonathan Lucroy for a wild pitch, allowing Devers to reach first base safely.

After Brock Holt's double put two runners aboard and brought the potential tying run to the plate, Treinen got Mookie Betts to ground out, scoring Devers. Treinen then retired Benintendi on a fly ball and Hanley Ramirez on a grounder to short to give the A's their fourth win in five meetings with the Red Sox this season.

Oakland won two of three from Boston at home in April.

Rodriguez (3-1) took his first loss of the year in eight starts, giving up Oakland's first three runs on six hits in five innings. He struck out four and did not walk anyone.

Chapman had two hits for the A's, who improved to 3-2 on a tough trip east that began against the New York Yankees and ends later this week in Toronto.

Benintendi collected three hits, including a double to complement his homer, while Xander Bogaerts and Mitch Moreland had two hits apiece for the Red Sox, who have lost five of eight, including two straight to open a seven-game homestand.

Both of Moreland's hits were doubles.

The Red Sox out-hit the A's 10-9.

--Field Level Media