Mariners 9, Royals 6: Jesus Montero went 3-for-4 with two RBIs as visiting Seattle got off to another fast start and went on to post its third win in four games.
Justin Smoak and Michael Saunders belted two-run homers for the Mariners, who held a 6-0 lead after two innings. Seattle owned a 7-0 advantage after two frames in Monday's series-opening 9-4 triumph.
Blake Beavan (4-6) tossed six-plus innings after being recalled from Triple-A Tacoma earlier in the day. Making his first start for Seattle since June 10, the right-hander allowed five runs and seven hits while striking out three.
Three relievers bridged the gap to Tom Wilhelmsen, who worked a perfect ninth for his eighth save.
Montero opened the scoring in the first with a two-out RBI double and Smoak followed with a blast just inside the foul pole in left field. It was Smoak's 13th homer and second in as many days.
Montero made it 4-0 with a two-out RBI single in the second and Kyle Seager drilled a two-run double to right field two batters later. Seager leads the American League with 31 two-out RBIs.
The Mariners posted their third three-run inning of the night in the fifth as Saunders launched his ninth homer of the season to straightaway center and Dustin Ackley added an RBI triple.
Ryan Verdugo (0-1) lasted only 1 2/3 innings in his major-league debut, surrendering six runs and eight hits. The 25-year-old left-hander was recalled from Triple-A Omaha to start in place of Everett Teaford, who pitched five innings of relief on Monday.
Pinch hitter Lorenzo Cain hit a two-run homer for the Royals, who fell to 1-4 on their 10-game homestand. Kansas City, which has dropped seven of eight overall, is a major-league worst 12 games under .500 at home (15-27).
GAME NOTEBOOK: Cain's homer was the second of his career and first since 2010 with Milwaukee. ... Less than 24 hours after the shortest start of his career, LHP Jonathan Sanchez was designated for assignment by the Royals. Sanchez, who lasted just 1 1/3 innings while allowing seven runs on Monday, went 1-6 with a 7.76 ERA in 12 outings this season. "We just felt change was necessary at this point and time," Kansas City general manager Dayton Moore said. "It's just one of those things that didn't work out." ... Seattle optioned RHP Steve Delabar to Triple-A Tacoma to make room for Beavan. Delabar went 2-1 with a 4.18 ERA in 30 relief appearances this year.