(Reuters) - Washington Capitals defenseman Mike Green will undergo abdominal surgery on Tuesday and be sidelined another four to six weeks, according to the club.

Green, once a key cog on the Capitals blueline, has battled injuries throughout the 2011-12 NHL season and appeared in just 10 of his team's 43 games.

It's basically a sports hernia but there were a couple parts to it, Capitals General Manager George McPhee told reporters on Tuesday.

One was a tendon issue, and one was a little tear in the stomach (lining). The tendon healed just fine, but the hole didn't close up ... It's never really healed to the point where he can play with it effectively.

McPhee said he expects Green, 26, to resume skating in a couple of weeks and be able to play in four to six weeks depending on how rehabilitation goes.

Green, who has three goals and six points this season, initially suffered what was thought to be a groin injury on November 11 in his first game back after being sidelined for six games with an ankle injury.

He missed the next 23 games before returning on January 3 at Calgary. He played only seven minutes in his next game, on January 7, and has been sidelined since.

Green, who is in the final year of a four-year contract that pays him $5.25 million annually, had a career-high 76 points during the 2009-10 NHL season.