Salvador Perez’s two-out double into the left-field corner in the 12th inning lifted the Kansas City Royals to a 6-5 victory over the Mariners Monday night at Safeco Field. It was  Seattle’s eighth consecutive extra-inning loss and 15th of the season, three more than the  team record of 12 set in 1982.

Alex Gordon drew a leadoff walk off reliever Lucas Luetge (1-3) in the top of the 12th and Emilio Bonifacio sacrificed him to second. After Eric Hosmer popped out and Johnny Giavotella walked, Perez sent Luetge’s first pitch into the corner, scoring Gordon with what became the winning run.

After the Mariners tied the game 5-5 in the eighth on back-to-back home runs by Michael Saunders and Franklin Gutierrez, Seattle had a chance to win  in the 10th when Kyle Seager opened the inning with a double and advanced to third on an error.

Seattle loaded the bases on intentional walks to Kendrys Morales and Saunders. Pinch hitter Endy Chavez lifted a fly to left. Seager tagged up, but Gordon’s throw to the plate nailed him on a close play when he was tagged on the elbow just before his hand touched down on the plate.

The Mariners (68-89) have lost 27 times this season in their opponents’ final at-bat. They have also lost seven of their past nine, 12 of 15 and 16 of 22 in September.

ARMS: Seattle starter Brandon Maurer pitched a season-high 7.0 innings but took a no-decision. He allowed one earned run on four hits. It was Maurer’s fifth quality start.

BATS: The back-to-back homers by Saunders and Gutierrez in the eighth marked the sixth time this season that Mariners have hit consecutive long balls and the first since July 1 when when Raul Ibanez and Morales did it against the Angels . . . Abraham Almonte, who went 1-for-5, has reached base in all 17 games he has played. He has hit safely in 15.

NOTES: LHP Joe Saunders, who lost to the Angels Saturday, is not expected to start again this season. Saunders finishes 11-16 with a 5.26 ERA in 32 starts.

NEXT: The series continues Tuesday with a 7:10 p.m. first pitch. Rookie James Paxton (2-0, 2.12) will make his Safeco Field debut against LHP Bruce Chen (8-3, 3.13).