SEATTLE -- Erik Swanson’s introduction to Major League Baseball got a little rough on Thursday as the Mariners' rookie right-hander gave up four home runs in three-plus innings to the Twins in an 11-6 loss at T-Mobile Park.

The Mariners have built their reputation on the long ball this season and added four more homers in the series opener, but the Twins teed off early and effectively as Jason Castro, Max Kepler, C.J. Cron and Byron Buxton all went deep before Swanson exited with no outs in the fourth.

• Box score

It was the first time since the stadium opened in 1999 that each team hit at least four homers in the same game. But the Mariners were outhit, 16-8, and committed a pair of errors that opened the floodgates to a seven-run fourth inning that sealed the game early.

“A handful of fastballs poorly executed in the middle of the plate, and guys took advantage of it and barreled them up and did some damage,” said Swanson, who has allowed 11 homers in six starts.

Seattle countered with a trio of homers off Twins starter Michael Pineda, but all were solo shots as the former Mariners right-hander evened his record at 3-3 with a 5.55 ERA in his first season back from Tommy John surgery.

Mallex Smith, Ryon Healy and J.P. Crawford hit the homers off Pineda and Daniel Vogelbach unleashed a three-run shot in the eighth for Seattle, which leads the Majors with 87 homers this season. However, the Mariners fell to 22-24 and 9-22 since their scorching start to the season.

Swanson, acquired along with fellow top pitching prospect Justus Sheffield from the Yankees in the James Paxton trade last December, fell to 1-5 with an 8.04 ERA after the shortest of his six starts in his first year in the Majors.

Manager Scott Servais was non-committal when asked if Swanson would make his next start, which would be Tuesday at Texas.

“We’ll see,” Servais said. “We have to look at where he’s at in his career. He’s in a spot where we brought him up and he’s had some good starts. He’s had some patches that have been very impressive, and you say this guy has a bright future ahead of him. But the consistency is the big thing. We’ll talk about it the next few days and see where he’s at going forward.”

The 25-year-old Swanson has had his moments since replacing an injured Wade LeBlanc in the rotation, but the Twins jumped on his fastball early with eight runs on nine hits before Servais brought in rookie reliever Parker Markel in the fourth.

The Twins are a fastball-hitting club that figured to be a tough matchup for Swanson, who left too many of his 91-92 mph heaters in the middle of the plate.

“I do like the fact that Erik Swanson does not back off,” Servais said. “He continues to hammer the strike zone and goes after them, and that’s a really good sign. One of the things with a young pitcher, once they get hit around a little bit, then all the sudden they back off. He continues to be aggressive and go after them. But the location of his pitches has to be more consistent.”

Mariners with their own power show

Smith, recalled from Triple-A Tacoma earlier in the day, broke an 0-for-24 skid dating back to before his demotion with his 398-foot homer in the third. Healy and Crawford went back-to-back leading off the fifth, with Crawford snapping an 0-for-11 stretch with a line-drive shot to right for his first home run with the Mariners and the fourth of his career.

“Healy had a great AB before me and then, thankfully, I was able to get a good pitch to drive and it went out,” said Crawford, playing his sixth game at shortstop since being called up from Triple-A Tacoma. “I’m just sticking to my approach and not trying to do too much.”

Vogelbach’s 399-foot homer in the eighth was his third in the past three games, raising his season total to 12, tied for the team lead with Jay Bruce and Edwin Encarnacion.

But the Mariners managed only four other hits and are now 5-20 against teams with winning records.