The Kansas City Royals rediscovered their postseason magic Wednesday night and won a battle of the bullpens en route to a 7-2 victory over the the San Francisco Giants.

Billy Butler snapped a 2-2 tie with a run-scoring single in the sixth, and the Royals added four more runs before the inning was over to break open a tight game and restore joy to their home fans in Kauffman Stadium.

"We needed to get something going," Butler told reporters after finishing with two hits and two RBI. "I felt like definitely it was a must-win for us."

"We had a couple big hits and the floodgates opened. It's big to get the series back even going back to their place."

After being thumped 7-1 Tuesday night in the series opener, Kansas City tied the best-of-seven series at 1-1 with Game 3 set for Friday in San Francisco.

With the series shifting to the home of the National League champions for the next three games, Wednesday's win was crucial to a Royals team coming off their first loss of the postseason after storming to the World Series with an 8-0 record.

San Francisco, vying for their third World Series title in five years, had it all their way in Game One behind ace left-hander Madison Bumgarner, who stymied a Kansas City franchise competing in their first postseason in 29 years.

The Royals turned it around in Game Two as Kansas City battered the vaunted Giants bullpen, while their own trio of shut-down relievers slammed the door on any comeback hopes. Giants starter Jake Peavy entered the night with the experience edge over the 23-year-old Yordano Ventura but Peavy was charged with four runs and chased in the sixth when San Francisco used five pitchers.

Salvador Perez delivered a two-run double during the rally, and Omar Infante blasted a back-breaking two-run home run that left the Giants fuming. The homer came against San Francisco's Hunter Strickland, who has allowed five in the playoffs.

As Perez crossed home plate, Strickland shouted in his direction and the two exchanged words as both dugouts emptied before the umpires intervened.

"When I got close to home plate he said 'get out of here,'" Perez said. "I said, 'why are you (shouting) at me?' Strickland said he was just angry at himself. "I don't know if he thought I was yelling at him or not. I wasn't yelling at him, I was just frustrated with myself," the Giants reliever said.

Perez did not think it was a big deal. "He started to get mad, so... forget about it." The sixth was an inning San Francisco would like to forget.

"That was a tough inning for us," said Giants manager Bruce Bochy. "(Strickland) is a really intense kid. That's probably an area where he is going to have to keep his poise."

A dreadful night for the Giants bullpen turned worse when pitcher Tim Lincecum was forced to leave with an injury during the eighth inning. Kansas City kept their cool throughout even as Ventura, firing 100-mph fastballs, yielded a lead-off home run to Gregor Blanco to start the game.

Butler tied the game with a single in the bottom of the first and the Royals took a 2-1 lead in the second on a double by Alcides Escobar. Brandon Belt forced another tie for San Francisco with a run-scoring double in the fourth before the Royals took command in the pivotal sixth.