Equipped with a one-run lead in the top of the ninth Monday night, Oakland A's closer Liam Hendriks allowed a homer and two doubles to consecutive batters, and the Kansas City Royals went on to close out a 6-5 win at the Coliseum.
Brett Phillips hit the tying home run off Hendricks and Adalberto Mondesi followed with an RBI double to end the Athletics' six-game winning streak.
Oakland's lead over Tampa Bay for the top AL wild card was cut to one game. Cleveland is 1 1/2 games behind the Rays.
Khris Davis' RBI single off Kevin McCarthy (4-2) gave Oakland a 5-4 lead in the eighth.
Phillips homered on a 2-0 fastball from Hendriks (4-3) with one out in the ninth, Hendriks' sixth blown save in 28 chances.
Whit Merrifield reached when center fielder Ramon Laureano allowed his drive to pop out of the pocket of his glove at the front of the warning track for an error. Mondesi sliced an opposite-field double to left.
Marcus Semien singled leading off the bottom half for Oakland but Ian Kennedy retired his next three batters for his 30th save in 35 chances, giving the Royals' Ned Yost his 1,200th win in 16 seasons as a major league manager. At 56-95, the Royals are trying to avoid their second straight 100-loss season.
Jorge Soler homered leading off the fourth, tying injured Los Angeles Angels star Mike Trout for the AL lead with his 45th home run.
Alex Gordon had two RBIs.