KANSAS CITY, Mo. — Jacob deGrom hadn’t given up more than six hits in a postseason start this year — and then the fifth inning of Game 2 happened.

It all came apart quickly for the right-hander, who had been able to sustain some fits of command issues in his previous playoff outings, but not against the Royals in a 7-1 loss in which deGrom was knocked out after five innings.

This wasn’t the first time deGrom didn’t have his best stuff in the postseason, but it was the first time he couldn’t overcome it. The right-hander was in position to become the first pitcher to win four games on the road in a single postseason.

But after the Mets spotted deGrom a 1-0 lead in the fourth, he nearly faltered in the bottom of the inning.

Ben Zobrist reached on an error by Lucas Duda at first and Juan Lagares couldn’t come up with Eric Hosmer’s fly to shallow center with one out for the Royals first hit. After Kendrys Morales grounded out, deGrom walked Mike Moustakas to load the bases.

After a visit from pitching coach Dan Warthen, deGrom got Salvador Perez on a slow chopper to short to get out of the jam.

DeGrom wasn’t as lucky in the fifth.

He walked Alex Gordon then allowed a single to Alex Rios before Alcides Escobar was unable to get a bunt down and instead came up with a run-scoring single to center to tie the game at 1-1.

But deGrom recovered to get Zobrist to ground out and Lorenzo Cain to fly to center, too shallow to score Rios from third.

That was undone when Eric Hosmer delivered a two-run single to center to put the Royals ahead for good.

DeGrom’s struggles didn’t go away after Hosmer, though, as Morales singled to right and Moustakas drove in another run with a single to make it 4-1.

He escaped the inning by getting Perez to ground out, but the damage had been done and deGrom’s night — and winning streak — was over.