May, ranked as the club's No. 8 prospect by MLB.com, was called up from Triple-A Rochester to make his highly anticipated big league debut against the A's, who have the best record in the Majors.
But May had trouble finding the strike zone, as only 28 of his 63 pitches went for strikes. He became just the second Twins pitcher to walk at least seven batters in two innings or fewer, joining Mike Cook, who walked seven in 1 2/3 innings on May 1, 1989.
"It was the case of a lot of things today," May said. "It was a lot of factors --some excitement, getting used to the ball. All kinds of stuff. But at the end of the day there's no excuses not making pitches when you need to and not executing."
It started out innocently enough for May, as his first pitch was a strike and resulted in an out with Coco Crisp popping out in foul ground. But Sam Fuld followed with a single before Josh Donaldson doubled and Brandon Moss walked to load the bases.
May walked Derek Norris to bring home a run, but was able to get out of the jam with the help of left fielder Josh Willingham, who threw out Donaldson at home as he tried to tag up on a fly ball from Josh Reddick.
The shaky first inning was harbinger of things to come, as May wasn't as fortunate in the second, walking five batters that inning and giving up three runs.
"The kid just had a hard time," Twins manager Ron Gardenhire said. "He couldn't gather himself. They took a lot of pitches and we walked a lot of people. That was pretty much the story. We couldn't throw the ball over. The kid had a hard time but he'll try again when it's his time the next time."
In the second, Donaldson brought home two runs with single after May issued three straight walks with two outs before Norris drew his second bases loaded walk of the game two batters later.
"After the first, I went in hoping to establish the strike zone in the second inning and wanted to get some quick hits," May said. "At that point it was a just a 1-1 game and I wanted to settle in. But I walked [Eric] Sogard and let it snowball a little bit. I got ahead of some guys and couldn't put them away."
Norris, who had five RBIs on the night, felt for May, as he understood his first-game jitters.
"All of us remember our debuts," Norris said. "Your brain can get scattered in several different ways. Some guys are able to harness it, and unfortunately the kid tonight, he just wasn't able to harness all the adrenaline, stuff that was going on."
May was able to get out of the inning without any further damage and was replaced by right-hander Samuel Deduno, who scuffled through three-plus innings in long relief. Deduno also had trouble with his control, walking three and allowing five runs on five hits.
All five runs allowed by Deduno came on homers, as Stephen Vogt connected on a two-run homer in the fifth and Norris crushed a three-run blast in the sixth.
"Sammy gave up a couple big ones but we tried to get through it as best as we could," Gardenhire said.
It backed A's right-hander Jeff Samardzija, who gave up two runs on seven hits over six innings to get his third win with Oakland since being traded from the Cubs in early July.
The Twins scored early on an RBI single from Trevor Plouffe in the first inning after Brian Dozier doubled with one out. Plouffe brought home the other run against Samardzija with an RBI groundout in the fifth.
Minnesota scored twice in the eighth against reliever Dan Otero, but it wasn't close to enough, and it handed the Twins their 12th straight loss to the A's dating back to Sept. 11, 2013. The last time the Twins lost 12 in a row to one team was in 2002-03, when they matched a club record by losing 13 straight to the Yankees.