– Righthander Alex Meyer has been transformed into a reliever — but he made his major league debut in the first inning on Friday.

It wasn’t a return to the starting rotation. It was in relief of Trevor May, who was bulldozed for six runs.

What a way to start a major league career, barely settling into your new uniform when the bell rings. And it wasn’t much of a first impression, as Meyer gave up four runs while the Brewers surged to a 10-4 victory at Miller Park in the opener of a three-game interleague series.

While the Twins saw the top-end stuff that made Meyer the No. 5 prospect in the organization, according to Baseball America, he also paid the price for falling behind in the count and becoming predictable. In 1 â…” innings, Meyer gave up four runs on three hits — including two home runs — with a walk and two strikeouts.

“Obviously, if you leave one over the middle of the plate it’s going to get hit,” said Meyer, whose parents, Dave and Sandy, and fiancé, Kyra Domingo, were in attendance. “It’s just a learning experience. Hopefully get the first one out of the way and the next time will be better.”

Still, his line was better than May’s. After Brian Dozier hit a leadoff home run off Kyle Lohse, the Brewers’ Gerardo Parra led off the bottom of the inning with a blast off May. And Milwaukee kept scoring.

The righthander gave up six runs, five earned, on six hits; he got one out, the shortest outing of his career. The first five Brewers to bat scored, and May made his own bed with a throwing error that allowed a run to score instead of a potential double play that would have ended the inning with the Twins only down 2-1. That’s why Meyer was summoned.

Meyer’s first pitch of his major league career was a 96-miles-per-hour fastball to Parra with one out in the first. He got Parra to fly out to right, and Jonathan Lucroy also flew out to right to end the inning. The second inning didn’t go as well.

Ryan Braun walked, stole second and went to third on a groundout. Meyer got ahead of Carlos Gomez and tried to finish him off with a slider away, but Gomez slapped it to right for an RBI single that put Milwaukee ahead 7-1.

Meyer then fell behind Aramis Ramirez 3-1 and came at him with a 95-mph fastball. Uh-uh. Ramirez belted it into the seats in left for a 9-1 lead. Meyer rebounded, getting ahead of Jean Segura and finishing him off with a slider off the plate. But then he threw a 2-1 fastball to Scooter Gennett, who began the day batting .198, and the second baseman homered to center for a 10-1 lead.

“We know his command is not where we hope it gets to at some point, but obviously it’s been better as of late,’’ Twins manager Paul Molitor said. “You can throw as hard as you want to, but if you don’t get ahead of hitters these guys are going to hit it, and they did.”

Lohse, on the other hand, was given a big lead and still threw changeups on 3-2 counts, something a young pitcher should note.

Meyer’s fastball was clocked at 94-96 mph with decent movement when thrown down in the strike zone. His slider, which is supposed to be a weapon, really snapped at times.

Joe Mauer scored on a fielder’s choice in the fourth and Trevor Plouffe hit a two-run homer in the sixth, but that was it for the Twins, who needed five pitchers to get through the game.

“We had to get 23 outs from our bullpen,” Molitor said, “which is not the way to start a road trip.”