KANSAS CITY — Royals starter Jorge López , who may be losing his grip on a spot in the rotation, had another rough outing in Kansas City’s 6-5 loss to the Yankees on Saturday night, which gave New York a doubleheader sweep.

The Yankees won the first game, 7-3.

Lopez gave up five runs and six hits in one-plus innings. Lopez had a scoreless first inning but couldn’t retire any of the six batters faced in the second inning.

Lopez was hurt particularly by his off-speed pitches — three times in the second inning he gave up hits on his curveball. A fourth hit came off his changeup.

“It was very poor,” Lopez said of his curveball. “I had the count and couldn’t finish them. They have been swinging the bats well.

“It could have been way different if I threw my curveball like [Jakob Junis] did in the first game. I couldn’t finish the execution and it hurt us. … That pitch is my out pitch. That’s why I didn’t go to any other pitch. I tried to do my best.”

When the damage was finally done, Lopez’s ERA ballooned to 6.79.

“A lot of times he was getting hurt with two-strike curveballs where he’s just got to learn to bury them,” Royals manager Ned Yost said. “In that situation, you want it to look like a strike and dive down out of the zone. It’s staying in the zone.”

Right-hander Glenn Sparkman, who may be next man up for a rotation spot, relieved Lopez and gave up just one run over 3 1/3 innings, allowing the Royals a chance to crawl back in it. The bullpen gave up just one run over eight innings.

“It was pretty special to be a part of that [bullpen effort],” Sparkman said. “But I did not have my command at all. I was fighting mechanics the whole three innings pretty much. I was trying to get in some type of a groove. I just kept battling, going at guys and working with what I had tonight.”

Added Yost, “[The bullpen was] really good. I feel real good about [Wily] Peralta’s performance in the first game. He came in and was banging nothing but strikes. [Kevin McCarthy] was good today for one-plus innings. [Brad] Boxberger was good. [Jake] Diekman was outstanding, and Ian [Kennedy] was very efficient with good stuff.”

Down 6-1, the Royals got one back on Adalberto Mondesi’s RBI double — Mondesi was thrown out trying for a triple.

The Royals got a break in the fourth when with one out, Hunter Dozier, who blooped an RBI double in the first inning, lifted a pop fly into short right-center that Brett Gardner lost in the twilight sky for a double.

Jorge Soler then sent a fly to deep right that Clint Frazier couldn’t track down — ruled an RBI double. Cam Gallagher then blooped an RBI single to right, making it 6-4.