BOSTON -- Mike Moustakas kept fouling off good pitches. He finally saw one he could handle and didn't miss it.
The Royals had two runners cut down at the plate in the ninth, one trying for an inside-the-park homer, and collected six hits against Boston closer Junichi Tazawa (2-6).
Moustakas capped off a 10-pitch at-bat with his go-ahead hit into the right-center field gap.
"A lot of great at-bats that inning," Moustakas said. "It ended up coming around to me and I was able to get the job done."
Moustakas also had a solo homer and RBI double for Kansas City, which salvaged a split of the four-game series.
Boston led 6-4 going into the ninth. After left fielder Jackie Bradley Jr. threw out Omar Infante trying for the homer for the first out, Kansas City rallied with four hits, tying it on Eric Hosmer's two-run single.
"There were some great at-bats," Kansas City manager Ned Yost said. "It was an awesome ninth inning for us. Just a succession of great at-bat after great at-bat."
Batting eighth in the final inning, Moustakas knew if he came up, the Royals were likely doing something special.
"I was hoping it would get to me," he said. "If it gets to me, we're going to be in pretty good shape."
Tazawa gave him everything he had.
"He was getting to all the pitches that were borderline," he said through a translator. "Fouling off a lot of pitches and I was dealing with a slippery ball. Obviously I was trying to get through, but he got the best of me."
Bradley Jr. had two RBI doubles and a single for the Red Sox, who went 6-4 on a 10-game homestand -- all under interim manager Torey Lovullo, who took over for John Farrell on Aug. 14. Farrell took a medical leave for the rest of the season to deal with Stage 1 Lymphoma.
"They hit some good pitches and it was not a typical Taz day," Lovullo said.
Boston trailed 4-2, but scored twice in both the sixth and seventh.
Royals starter Edinson Volquez gave up six runs in 6 2/3 innings.
Trailing 2-1 in the fourth, the Royals scored twice, taking advantage of two errors on one play. Second baseman Josh Rutledge booted a grounder and center fielder Mookie Betts' throw bounced into the Royals' dugout for the first run. Moustakas followed with his RBI double. He homered into the Green Monster seats.
Boston starter Eduardo Rodriguez allowed four runs -- two earned -- in six innings.
Royals: C Salvador Perez had the day off. He took a hard foul tip off the mask and one off the right leg Saturday night, but was feeling fine.
Red Sox: Utility infielder Brock Holt was out of the lineup again Sunday. He was set to play Saturday, but was taken out of lineup after batting practice with a strained left oblique. ... OF Hanley Ramirez had the day off.
WHAT A THROW
Yost was still praising Bradley's peg from left-center in the ninth, even saying he wanted third-base coach Mike Jirschele to send Infante.
"I was screaming, 'Send him,'" he said. "I said, 'It's not on you.' It was just a great throw. He's got a tremendous arm."
NAILED AT HOME
Besides Infante, Kendrys Morales was cut down at home 8-4-2 for the final out of the ninth.
A light mist started falling early and remained for most of the game.
Royals: RHP Kris Medlen (1-0) makes his first start since returning from Tommy John surgery Monday when the Royals host the Baltimore Orioles. RHP Ubaldo Jimenez (9-7) is set to start for the Orioles in the first meeting since the Royals swept the ALCS.
- Home Plate Umpire - Mike Everitt
- First Base Umpire - David Rackley
- Second Base Umpire - Bob Davidson
- Third Base Umpire - Hunter Wendelstedt