DETROIT -- The pain in Dan Cleary’s left knee started in September and would come and go for the next eight months. At times, walking up a flight of stairs was a chore.

It explains, to a large degree, why the 31-year-old Detroit Red Wings forward struggled much of the season.

Cleary had surgery Tuesday to repair two tears in his meniscus.

“They cleaned it up, and it’s a lot better now,’’ Cleary said Wednesday. “You want to go into the season healthy. It’s tough for me to play my game when I’m hurt.’’

He will start lifting weights Monday and begin full workouts in a couple weeks. He expects to be fully recovered well before training camp in September.

Cleary missed four weeks with a separated shoulder in the middle of the season. He tore his groin muscle twice, which he thinks was related to his knee issues, forcing him to miss six games late in the season.

He wasn’t able to skate as well as he normally does and finished with 15 goals and 19 assists in 64 games and just two goals and no assists in 12 playoff games.

In hindsight, it would have been best for Cleary to get his knee taken care of during the season. But it would have been difficult for him to sit out when the team was ravaged by injuries and scrapping for valuable points.

He’ll work out with team trainer Piet Van Zant until July, before leaving for southern California to begin his annual training program with T.R. Goodman.

Cleary called it an important offseason. He expects to return to his 20-goal form of 2006-07 and ’07-08.

“I want to be an important player on the team and have proven that I can be,’’ Cleary said. “My goal is to get better each season. I’ll train real hard this summer and will make sure I have a good season.’

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Cleary has spoken several times with Jiri Hudler, one of his California workout partners, who is returning to the Red Wings after spending one season in Russia.

“He’s real excited, looking forward to coming back,’’ Cleary said. “He’s an important player, adds another element.’’

Cleary has not spoken to Nicklas Lidstrom lately but, like most in the organization, he is confident the captain will return next season.

“He’ll be back,’’ Cleary said. “We don’t have to worry about that.’’

Cleary noted this is the first time in three years he has sat at home in May instead of play hockey.

“I think everyone is looking forward to some redemption next year,’’ Cleary said.