HOUSTON — All of the momentum from Whit Merrifield’s grand slam in the seventh inning Wednesday afternoon slowly shifted over to the Astros’ dugout over the next three innings.

Houston mounted a comeback against the Royals’ bullpen with runs in the eighth and ninth innings before Jake Meyers’ grounder off reliever Joel Payamps in the bottom of the 10th scored Alex Bregman, handing Kansas City a 6-5 walk-off loss at Minute Maid Park.

After beginning the 10th with Bregman as the automatic runner at second base, Payamps allowed a single to Kyle Tucker. Tucker took second on catcher’s indifference, then Meyers hit a chopper back to Payamps that deflected off the pitcher. Payamps threw to first as Bregman scored.

The Royals faced the Astros seven times over the past 10 days, and the bullpen held one of the best offenses in baseball quiet for six of those games. The unit entered Wednesday having posted a 1.89 ERA (four earned runs in 19 innings) against the American League West leaders.

On Wednesday, the Astros finally got to the Royals’ relievers, handing Kansas City its second loss in a row and a series defeat.