ST. PETERSBURG, Fla -- Kevin Kiermaier said he's trying to simply his approach at the plate and do less with the ball. But for the Tampa Bay Rays center fielder, it seems like less is more.

Kiermaier hit the go-ahead home run in the bottom of the sixth inning to lift the Rays to a 3-2 win over the Kansas City Royals on Sunday at Tropicana Field.

The Rays' bullpen combined for four shutout innings, with Xavier Cedeno (3-1) earning the win. Brad Boxberger pitched a perfect ninth inning for his 32nd save of the season.

Luke Hochevar (1-1) took the loss for Kansas City, which failed to sweep the season series against the Rays.

"Good win, exciting ballgame," Rays manager Kevin Cash said. "It was obviously a well-pitched baseball game. (Nathan Karns) really set the tone, did a nice job for us. Our bullpen came in, did a nice job. It was a good win. We needed this one and glad we got it."

The Royals had a chance to tie with runners on first and third with one out in the top of the eighth inning against Rays reliever Alex Colome. Designated hitter Kendrys Morales hit a slow chopper down the first base line that appeared to be foul. But Rays first baseman James Loney fielded the ball and threw to catcher Rene Rivera, who tagged Ben Zobrist out at home and then tagged Morales, who never left the batters' box for a 3-2 double play.

Loney also made a nice defensive play in the ninth inning on a sliding catch of a pop fly from left fielder Paulo Orlando that drifted into foul territory.

"Those two plays from James pretty much decided the ball game," Cash said. "On the foul ball it was a close on the line there. I couldn't tell if it was fair or foul but it's the umpire's call."

Royals manager Ned Yost clearly disagreed with the call.

"If you go back and look at the replay, obviously it's (foul)," Yost said. "We generally don't run on foul balls. It was a foul ball. So when (Morales) hits it, he sees that the ball is foul. It's not a play you instinctively run on."

Morales believes such plays should be allowed to be reviewed.

"It is a little bit frustrating," Morales said through an interpreter. "The game shouldn't be decided on a play like that. The game shouldn't end that way."

Tampa Bay (64-66) opened the scoring in the bottom of the first inning when right fielder Brandon Guyer scored on a RBI single from left field Joey Butler to give the Rays a 1-0 lead.

Kansas City scratched across two runs in the top of the third with RBI singles by Zobrist and center fielder Lorenzo Cain. The Royals loaded the bases with two outs, but Rays starter Nathan Karns escaped the jam by getting third baseman Mike Moustakas to ground out to first.

"I didn't have my best stuff with me today, but I felt like I was able to make pitches when I was able to," Karns said. "That was my objective today, make pitches whenever I could."

The Rays tied the game at 2-2 in the bottom of the third when Guyer hit his sixth home run of the season off Royals starter Danny Duffy.

"My first at bat I was trying to go out there aggressive and it worked out because I was able to see all his pitches," Guyer said. "I worked a long at bat and that always helps the next couple at-bats because you can see the plane they're on, how it comes out of his arm, so I think that helped out a lot today."

Karns gave up two runs on six hits and struck out five on 91 pitches (58 strikes).

Duffy gave up two runs on seven hits and struck out six on 99 pitches (70 strikes).

"I just threw a lot of pitches in the first," Duffy said. "It cost me from going deeper into the game. There's going to be times when you are going to go out there and have a bad inning, and it happened to be the first today, you know?"

GAME NOTES: Royals RF Alex Rios, who was removed from the lineup Saturday, is back in Kansas City with what manager Ned Yost says is an illness. Yost does not expect Rios to go on the disabled list. ... Rays C Rene Rivera, who bruised his lower lip Saturday as result of being hit by a pitch from Royals RHP Kris Medlen, was back in the lineup Sunday. ... Royals RHP Ryan Madson has been shut down since Aug. 22 because of a dead arm. Yost expects him to be fine but he did not pitch Sunday. "He's progressing," Yost said. "With rest he'll be fine." ... Rays manager Kevin Cash said LHP Matt Moore should get some turns in the rotation when he rejoins the team in September. Moore was sent down to Triple-A Durham after going 1-3 with a 8.78 ERA in his first starts after returning from Tommy John surgery.