Alcides Escobar opened the fourth with a single to right off Roenis Elias (4-5), who had retired the first nine batters. Moustakas followed with his seventh homer over the right-field wall.
The Royals would score five more, all with two outs. Infante unloaded the bases with his double to left, then Jarrod Dyson and Escobar each followed with left-field RBI doubles.
Escobar had three hits – two in the fourth – and scored twice. Moustakas had three hits and two RBI. Infante also had three hits to go along with his three RBI.
The Royals, second in the majors in batting average, pounded out 13 hits.
Austin Jackson and Mike Zunino each had two hits for the Mariners.
Danny Duffy, in his first start for Kansas City since a rehab stint, was one out away from being the pitcher of record but couldn’t close the fifth. He gave up a sacrifice fly to newly promoted Franklin Gutierrez and another run scored on an error.
Ryan Madson (1-1) worked 1-plus inning of hitless relief for the win.
This was the 42nd game in 44 days for the Mariners. They get their first day off Thursday since June 8.
Mariners: RHP Hisashi Iwakuma (strained lat) will have his second rehab start Thursday for Triple-A Tacoma. He is expected to throw between 70 and 75 pitches. He likely will have one more before the club considers his next step. LHP James Paxton (strained middle finger) will play catch Thursday. “That’s a step in the right direction,” manager Lloyd McClendon said.
Royals: CF Lorenzo Cain slightly strained his hamstring running down a Dustin Ackley flyball in the seventh inning Tuesday. As a precaution, manager Ned Yost held him out to give him two full days (off day Thursday) to rest it.
UP NEXT (Friday)
Mariners: RHP Taijuan Walker (5-6, 4.94) doesn’t have a winning record but that’s not relative the way he’s trending. Over his last five starts, Walker is 4-1 with a 2.04 ERA, has won three straight and has gone eight innings in back-to-back starts. Something has clicked for the second-year right-hander.
Angels: RHP Matt Shoemaker (4-5, 5.20) has not found what he had last season when he went 16-4 with a 3.04 ERA. He has split with Seattle this year, winning 5-3 in his first season start April 8. He then lost 3-2 on May 4. In that game, he worked a season-high 7 1/3 innings with a season-high 10 strikeouts but yielded three home runs.
BIG THREE OF SORTS
Walker, Elias (before his start Wednesday) and rookie Mike Montgomery have stepped up since Mariners veteran starters Iwakuma and James Paxton landed on the DL. Over each of their previous three starts (9), they were a combined 7-1 record with a 4.71 ERA, 14 walks and 43 strikeouts. “It’s a big lift when you think Iwakuma and Paxton are out X amount of time,” McClendon said. “If I had hair I’d be pulling it out. These guys have come in and thrown some quality, quality innings and really settled our rotation quite nicely.”
The Royals have not built the third best record in the American League by facing left-handers. They were 10-13 before facing Elias and had lost seven straight.
They chased Elias in the fourth inning and went on to their first win against a left-handed starter since May 17.