KANSAS CITY, Mo. – It was epic, it was stunning and it came – of course – against the hard-charging Kansas City Royals.

The question now, as the Sox sort through the rubble of the biggest Royals comeback ever is, how much recovery power will they have after watching the a rally against, David Robertson and Tommy Kahnle – who tried but failed to rescue the $46 million closer – for seven runs in the ninth inning of an 8-7 debacle?

It came the day after the bullpen blew a three-run lead to start a nine-game road trip. It was the Sox’ fifth loss in a row and 13th in their last 17 games and it left more than a couple players sitting at their lockers in stunned silence, a scene more common in late August or September than late May.

“When they won, I was like, ‘This is true?’ I can’t believe it,’’ Sox left fielder and former Royal Melky Cabrera said. “I just can’t believe it.”

Nor could a Sox fan base that saw its team storm to a 23-10 start and six-game lead in the American League Central. As the Cleveland Indians, who took three of four from the Sox at U.S. Cellular Field to start the week, won in Baltimore to knock the Sox out of first for the first time since April 22, “fire Robin Ventura” petitions were circulating on the Internet.

“You get to that ninth, and the way games have been going, you go to the guy to close it out, because we haven’t been able to get to him,’’ said Ventura, noting Robertson’s light workload of four appearances in the last 18 days and his first in five days. “There’s no time clock. If you can’t close it out, that’s what happens. And today we couldn’t close it out.’’

With Nate Jones having warmed up in the seventh, Ventura was reluctant to get him back up again to bail out Robertson. In excruciating real time, the Royals pecked away after Robertson retired the first batter and put together a stunning rally capped by Brett Eisner’s smash past first baseman Jose Abreu against Kahnle with the bases loaded. Kahnle’s pitch, his 10th in the at-bat to Eisner, was a 98-mile per hour low fastball on the outside corner.

The inning also included a double to the right field wall by Eibner that right fielder Adam Eaton lost in the sun, a bases loaded walk to Alcides Escobar by Robertson after being in a 1-2 count, a single by White Merrifield off Robertson’s glove that deflected into right field (likely negating what would have been a double play ball to second baseman Brett Lawrie) and RBI double by Eric Hosmer that made it a one-run game.

Kahnle relieved Robertson and catcher Drew Butera – who had replaced an injured Salvador Perez — doubled in the tying run. After a couple of intentional walks and a wild pitch, Eibner delivered the game-winner.

“They put good at-bats together and I couldn’t find the strike zone for a second and one thing leads to another and you end up giving up six earned runs and blowing a chance for us to get a win,” Robertson said.

Robertson is always hard on himself after a blown save, but he seethed after this one, which wasn’t even a save opportunity.

“It doesn’t matter what the score is,’’ he said.

“Everyone did their job except me. It’s a tough one to take. I blew the game.’’

And the defending world champion Royals (25-22), injury depleted or not, got the recharge they needed after a lackluster start.

“They have mojo over there right now,” Sox catcher Alex Avila said. “They just keep coming at you and taking advantage of the fact that we’re scuffling a little bit right now.”

There are losses, there are tough ones and there are historic ones. This one will be tough to recover from, although having Chris Sale pitching Sunday can’t hurt.

“It might have a lasting effect,’’ third baseman Todd Frazier said. “There are going to be some guys who are in here who tonight aren’t going to be real happy.’’