MINNEAPOLIS — The Minnesota Twins were hoping Josh Willingham would be able to avoid surgery on his injured left knee, which has hobbled their slugger for the last few weeks.

They found out after the Twins lost 7-3 to the New York Yankees on Tuesday night that Willingham will miss four to six weeks for an arthroscopic procedure to get him well, the latest in what is fast becoming a long line of disappointments for the Twins this season.

Willingham was placed on the 15-day disabled list and is scheduled to have surgery on his torn meniscus on Wednesday. and he said he will miss the next four to six weeks while recovering.

“We knew at some point, whether it be at the end of the year, that I was going to have my knee cleaned up,” Willingham said after the game. “What made sense this time was the timeframe that the bone bruise was going to take to heal. I was going to miss three weeks minimum for that, and that’s three weeks recovering time.”

Willingham also has a bone bruise on the knee, and team doctors told him it would take a minimum of two weeks, but likely closer to four, for that to heal. Since he was already going to be on the disabled list, Willingham and the doctors felt the time was right to have the surgery as well to repair a meniscus tear that had grown bigger in recent days.

“I could have rehabbed the bone bruise and come back and played and maybe been fine, I don’t know,” Willingham said. “I could have hurt it the next week and ended up having surgery then. It was a hard decision.”

Samuel Deduno (4-3) gave up three runs on five hits in six innings for the Twins, another strong outing for one of the breakout stars from the World Baseball Classic.

But Yankees starter Phil Hughes (4-7) put the Twins offense on ice, giving up one run on six hits in seven innings.

Brian Dozier had an RBI double in the ninth inning and Joe Mauer drove in a run with a single in the third. But the Twins bullpen faltered again, with Anthony Swarzak giving up four runs in the seventh, three of which came on a homer from Robinson Cano that broke the game open.

“Deduno gave us an opportunity and I like what he did,” Twins manager Ron Gardenhire said. “Unfortunately we missed our opportunities.”

Willingham has been bothered by the sore knee for some time, and the last straw came when he felt increasing discomfort during pregame warmups on Monday night. He had an MRI on Tuesday that revealed the tear, but GM Terry Ryan said earlier in the day that he didn’t think Willingham would need to have surgery during the season.

Everything changed when Willingham met with the doctors, and now he is hoping that they have pinpointed the issue that has been plaguing him during a rough start to the season.

Willingham has struggled coming off of a career year in 2012. He is hitting .224 with 10 homers and 37 RBIs, and the Twins think some time to rest may be just what he needs to regain the power-hitting form he had last season when he hit 35 homers and drove in 110 runs.

Willingham first tweaked his knee while sliding on a stolen base attempt, and he’s been bothered by it for much of the last few weeks. He tried to take a shot to relieve the pain, but that was ineffective.

“I know it’s going to fix the problem that’s been causing me trouble,” Willingham said. “Hopefully that will clear it up and I can play without any pain.”

The 34-year-old, who signed a three-year, $21 million contract before last season, tried to play through the pain. But it all came to a head on Monday night as he tried to warm up for the game. He was scratched from the start and placed on the disabled list less than 24 hours later.

“I’ve been sort of battling it for a while and then I hurt it again on Friday night,” Willingham said. “I took a couple days off and tried to run last night, and it just wasn’t happening.”

The injury depleted an already thin Twins outfield and left them with few options. Struggling rookie Aaron Hicks was recalled from Triple-A Rochester to replace Willingham. Hicks got off to a horrendous start after making the jump from Double-A to the majors, then went on the disabled list with a hamstring injury.

The Twins were hoping to let Hicks get some extended at-bats in Triple-A to rebuild his confidence before recalling him, but the injury to Willingham derailed those plans. Hicks hit .190 in six games for the Red Wings since being activated, but did have two hits on Tuesday.

NOTES: The Twins have lost eight of 11 games. … Deduno went at least six innings for the fifth straight time. … Mauer snapped an 0-for-18 skid with his single in the third. … The Yankees will send LHP CC Sabathia (8-6, 4.15) to the mound for Game 3 on Thursday against RHP P.J. Walters (2-4, 6.03).