KANSAS CITY, Mo. – Justin Maxwell homered in the second inning, then singled twice in a six-run sixth inning Friday night as the Kansas City Royals rallied for a 9-6 victory against the Boston Red Sox.

The Royals have won 15 of 17 games to move seven games above .500, matching their best record of the season.

Maxwell, acquired July 31 by the Royals from the Houston Astros for a minor league pitcher, homered leading off the second.

With the Royals trailing 6-3 in the sixth, he led off with a single. The Royals sent 11 men to the plate in the inning against Red Sox pitchers Jake Peavy, Drake Britton and Pedro Beato.

Peavy, who was making his second Red Sox start since being acquired in a July 30 trade from the Chicago White Sox, yielded singles to Maxwell, Mike Moustakas and Alcides Escobar to start the inning. Escobar’s RBI single finished Peavy.

Eric Hosmer’s two-run single with two outs off Britton put the Royals on top 7-6. David Lough contributed a sacrifice fly and Billy Butler doubled home Hosmer. Maxwell’s second single in the inning scored Butler with the final run.

Mike Napoli, a career .368 hitter off Royals right-hander Ervin Santana, hit a three-run double with two outs in the third for Boston.

That ended Santana’s night. He gave up six runs on nine hits, including David Ortiz’s 22nd home run in the third, in 32/3 innings, his shortest outing of the season.

Peavy lasted five innings, plus three batters, allowing six runs on 10 hits.

Francisley Bueno (1-0), who was promoted Thursday from Triple-A Omaha, picked up the victory with 21/3 scoreless innings. He has two big league wins, both against the Red Sox. Britton (1-1) was charged with the loss.

The Royals had a 16-hit offense, included three hits each by Butler, Hosmer and Maxwell. Alex Gordon had two hits, including his 12th home run.

Greg Holland worked the ninth for his 31st save in 33 chances.

NOTES: Royals catcher Salvador Perez is progressing in his on-the-field activities and is hopeful he’ll get clearance to play Sunday.