Greg Stiemsma #54 of the Boston Celtics looks on during warm ups against the New Jersey Nets at Prudential Center on April 14, 2012 in Newark, New Jersey. (Photo by Chris Chambers/Getty Images)

BOSTON (CBS) – While the Boston Celtics have been doing their best to retain their own free agents, it appears one is close to getting away.

It looks as though center Greg Stiemsma, who played well on the defensive end as a rookie in 2012, could be heading to the Minnesota Timberwolves in the near future, according to ESPN Radio in Minnesota.

“The Wolves expect to get restricted free agent center Greg Stiemsma,” writes Darren Wolfson of 1500AM in the Twin Cities. “Boston is over the cap, so the Wolves feel like they will be able to structure the contract in a fashion such that Celtics general manager Danny Ainge won’t be able to match.”

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The Celtics are a little hamstrung by the salary cap at the moment as they are still working to finalize deals with Jason Terry and Jeff Green. Should the Wolves offer Stiemsma a contract that exceeds the bi-annual exception ($1.957 million annually over two years), the Celtics will not be able to match it.

However, there is still a chance Stiemsma could accept a lower offer to remain in Boston.

While the loss of Stiemsma would hurt the Celtics’ depth at center, they have Chris Wilcox returning after missing the end of last season with a heart ailment, along with rookie Fab Melo. There also remains the chance Kevin Garnett could see some time at the five, much like he did last season.

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In 55 games last season, including three starts, Stiemsa averaged 3.2 rebounds and a team-leading 1.5 blocks per game.