KANSAS CITY, Mo. — The Kansas City Royals whipped out the same formula that carried them to last year’s World Series to turn back the Houston Astros and tie their AL Division Series at a game apiece.

Some clutch hitting. Stingy defense. An unflappable bullpen. Even a little help from replay.

“Just battling,” first baseman Eric Hosmer said. “That’s what this team does so well.”

The Royals rallied from a three-run deficit Friday, getting a go-ahead single from Ben Zobrist in the seventh inning, and then watched Wade Davis and the bullpen make it stand in a 5-4 victory that brought back memories of their nip-and-tuck postseason of a year ago.

The Royals knotted the game at 4 off Scott Kazmir and relievers Oliver Perez and Josh Fields in the sixth. Kansas City took the lead in the seventh when Alcides Escobar led off with a triple against Will Harris (0-1) and Zobrist followed with his single through the left side.

Kelvin Herrera (1-0) and Ryan Madson each tossed a scoreless inning for the Royals, and Davis came on to close it — though the real drama was only beginning.