Seattle ? As if a losing a fourth straight game weren’t bad enough, the Royals also had one of their best players go down with an injury on Saturday.

Third baseman Mike Moustakas sprained his right knee during Kansas City’s 4-3 loss to the Seattle Mariners. Moustakas, who is second on the team in home runs and RBIs, is day to day while awaiting the results of an MRI.

Moustakas dove to his right in the first inning to smother a hard grounder by Casper Wells. Moustakas rolled over and threw from one knee with his body on top of the foul line and well behind the third-base bag.

The throw was just late. Moustakas left the game afterward and the Royals aren’t sure when their No. 3 hitter will be back.

“I must have twisted my body around a little too much and felt a little something in my knee,” Moustakas said. “I put a little pressure on it when I was walking around, felt Ok, but (manager) Ned (Yost) wanted to get me out of there. Training staff took a look at me and did a good job, so it feels good for right now.”

After consecutive nights of hapless offense, the Royals did receive a dose of luck in the top of the ninth, but couldn’t cash in.

Lorenzo Cain’s generic fly ball headed out to right field, and it looked like the Mariners were a simple catch from a third consecutive win.

But, Cain’s fly soared into the sunlight. Seattle right fielder Wells paused, waiting for the ball to drop low enough so he could see it, then sprinted toward the line. The sure out on a cloudy day tailed away from him and dropped for a triple to score a run and put the tying run at third in the top of the ninth.

“It can get thick quick,” Seattle manager Eric Wedge said.

No matter. Seattle closer Tom Wilhelmsen remained steady and got a ground ball from Alex Gordon to end the game.

“He probably hit it in the best spot you could possibly hit a ball,” Wells said. “I’m glad Tom got out of it because I wouldn’t have had a good afternoon after that.”

Wilhelmsen’s 13th save was a result of just enough offense from Seattle. Mike Carp’s eighth-inning sacrifice fly ended up being the difference, and made a winner out of Kevin Millwood (4-8), who pitched into the seventh without allowing a run.

Millwood threw 6 1/3 innings, gave up six hits, struck out three, walked one and was aided by two big defensive plays from shortstop Brendan Ryan.

It was all needed to supplement Jesus Montero’s two-run homer in the third, his 10th of the season. Montero whacked the first pitch he saw from Kansas City starter Bruce Chen (8-8) into the bullpen for a 2-1 Seattle lead. Chen lasted six innings, allowed seven hits and three earned runs.

Wells wasn’t the only one battling the sun. Gordon turned Kyle Seager’s fly ball into a double when he lost it in the sky following Montero’s homer. Miguel Olivo followed with a single to right, and the Mariners decided to challenge the arm of Jeff Francoeur, who came into the game leading the league in outfield assists. Seager slid wide and tapped the plate with his hand to put Seattle up 3-1.

After taking their lumps early the past two days, Kansas City took a first-inning lead when Billy Butler, who was 3 for 3, singled to right to score Alcides Escobar. Butler singled again in the fourth and sixth. He has seven hits in the first three games of the series.

The Royals crept back into the game after Escobar’s one-out triple brought home Gordon, who had doubled off Brandon League in the eighth. But Chris Getz, who was hitting for Moustakas, grounded out to second against a drawn-in infield. League then intentionally walked Butler and Yuniesky Betancourt grounded out to third to end the inning.

Getz came in to play second and Betancourt moved to Moustakas’ spot at third following the injury. Getz dropped a soft fly ball on his first fielding chance and Betancourt dropped a throw at third in the eighth, allowing the Mariners to load the bases with none out.

Saturday’s loss was the fourth consecutive on the road for Kansas City, which is 1-6 against Seattle this season.