Now that New England quarterback Tom Brady has signed an extension, Lions quarterback Matthew Stafford’s cap hit for the 2013 season ($20.3 million) is the third highest in the NFL behind Denver’s Peyton Manning and Giants’ Eli Manning per ProFootbalTalk.com.

 However, that should not be for long.

 Lions president Tom Lewand confirmed two weeks ago that the Lions will try to extend Stafford beyond the 2015 season.

 Lewand said the reason was to keep Stafford in Detroit more than to give the team salary cap space.

  Sounds good, but cap space is needed.

  Preliminary talks with Stafford’s agent and the Lions have begun per Albert Breer of the NFL Network.

  It’s a somewhat similar situation to the extension of Calvin Johnson a year ago which also gave the Lions salary cap relief. Johnson’s deal was finished in early March. 

 NFL free agency starts March 12.

 Stafford signed a six-year, $72 million contract when he was the first overall pick in the draft in 2009.

 (Join Lions beat writer Paula Pasche for a live chat at 3 p.m. Thursday.)