Rookie catcher MJ Melendez homered and drove in six runs, and Brad Keller ended a three-start losing streak as the host Kansas City Royals defeated the Boston Red Sox 13-5 on Sunday.
Melendez's three-run blast off Red Sox starter Kutter Crawford in the fifth inning broke open a two-run game.
In the series, Melendez homered three times and drove in 10 runs as the Royals won three of four. The Red Sox have lost four of their past five games.
Keller (6-12) worked six innings, allowing four hits and one run -- Rafael Devers' 24th homer of the season. Keller walked three and struck out four.
Crawford (3-4) surrendered five runs, one on a balk, on five hits and two walks. He struck out four.
In the fifth inning, Michael Massey walked for the Royals, and Nate Eaton doubled on a long fly ball to center that Jarren Duran allowed to drop just past him on the warning track, putting runners at second and third.
Crawford got a strikeout, but Melendez's 13th homer of the season extended the Royals' lead to 5-0.
Devers homered in the sixth, and Tommy Pham, who was batting just .150 in his first five games with Boston, hit a two-run homer in the seventh off Taylor Clarke to pull the Red Sox to within 5-3.
Kansas City added two insurance runs in the bottom of the seventh on back-to-back triples by Eaton and Kyle Isbel and Melendez's sacrifice fly.
Eaton's triple was a routine fly ball in shallow center that Duran lost in the sun, and Isbel's was a long fly ball that Duran couldn't grab as he hit the fence in right-center field.
Duran, who was being heckled by fans in the seventh, appeared to take a few steps toward the fence in response to the fans. Right fielder Alex Verdugo came over to try to calm Duran.
Kansas City took advantage of four walks by Darwinzon Hernandez to add six runs in the eighth on a two-run single by Massey, a two-run double by Isbel, Melendez's sacrifice fly and Bobby Witt Jr.'s RBI single.
Duran's groundout and Pham's single brought in two runs for the Red Sox in the top of the ninth.
The Royals had 11 hits -- with Melendez, Massey, Eaton and Isbel each slashing a pair -- to Boston's 10. Isbel drove in three runs and scored three, and Massey and Eaton each scored three times.
For the Red Sox, Pham had two hits and three RBIs, and Reese McGuire had two hits.
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