Martin Mayhew’s hands are tied in an effort to get Ndamukong Suh signed to a contract extension to clear salary cap space.

Suh fired his long-time agents several weeks ago and has not hired a replacement, Mayhew said on Friday morning.

“I talked to him about a week ago (and said), ‘We’re going to be at the Combine next week. I don’t want to rush you on the agent thing, if you have one by then it would be nice,'’’ Mayhew said.

Then Mayhew called him on Thursday and Suh told him he’s close, but still hasn’t decided on an agent.

Suh’s current contract would count $22.4 million  against the salary cap in 2014. An extension would free up much needed space.

“If you go back to the last two that we did that were big deals, that were extensions with Matthew (Stafford) and Calvin (Johnson), Matthew’s was done after the start of free agency. Calvin was done on the eve of free agency,’’ Mayhew said. “I wouldn’t be surprised if this would happen the same way.’’

Mayhew doesn’t seem to be concerned about getting a deal done. There are no plans to trade the defensive tackle who was a first-round pick in the 2010 draft.

“I anticipate we’ll get something done. He has said he wants to be here, we’d like him to be here,’’ Mayhew said. “That’s my mindset right now.’’

Still Mayhew said he has enough cap space to get done what he wants to in free agency even if a Suh deal is not done. That includes getting a deal done with tight end Brandon Pettigrew. Teams can start talking to free agents on March 8 and can sign them on March 11.

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