Olson's 12th homer of the season highlighted a four-run eighth inning for the A's, who took two of three from the Royals. Olson has four home runs and nine RBIs in his past four games.

With the score tied 1-1, Oakland's Dustin Fowler led off the eighth inning with a single and then stole second. Jed Lowrie brought Fowler home with a single up the middle to give the A's a 2-1 lead and knock Kansas City starter Jakob Junis out of the game.

Reliever Burch Smith walked the first batter he faced, Khris Davis, and Olson followed with his three-run shot.

The Royals' Jon Jay hit his first home run of the season, a solo shot in the third inning that tied the score 1-1.

Jonathan Lucroy had an RBI single that scored Mark Canha to give the A's a 1-0 lead in the top of the third inning.

Junis (5-5) pitched 7 1/3 innings, his second-longest start of the season. He was charged with three runs on six hits and one walk while recording a career-high nine strikeouts.

Oakland starter Daniel Gossett pitched well, allowing only one run on two hits with a strikeout and two walks in five innings.

Lou Trivino (3-0), Yusmeiro Petit and Blake Treinen combined to throw four scoreless innings in relief for Oakland. Treinen retired the Royals in order in the ninth inning in a non-save situation.

The A's stay on the road and head to Texas to start a two-game series with the Rangers on Tuesday before returning to Oakland for a 10-game homestand.

The Royals head west for their next seven games, beginning with a three-game series with the Los Angeles Angels that gets going Monday.

--Field Level Media