Time may be on their side, but Matthew Stafford may not be if the Detroit Lions can't come up with a deal agreeable to both parties.

The Lions are engaged in contract negotiations with Stafford, who is entering his fifth season with Detroit in 2013. Lions president Tom Lewand told the Detroit Free Press that the talks could be tabled until after the season if a deal isn't done soon.

"We've still got some discussion to have, but at some point in time we'll either get a deal done or we'll focus on football," Lewand said to the Free Press. "It's a different dynamic when you have two years left on a contract versus one. Most of them get done with a year left. And we've worked through a lot of those issues and continue to do that, want to continue the dialogue. But at some point in time we'll either have a deal or we'll agree that the focus needs to be on what's going on the field."

Stafford and the Lions began talks in February, but the negotiations didn't become serious until April, according to the Free Press.

Stafford has two years left on the six-year contract he originally signed as the No. 1 overall pick in the 2009 draft. He reportedly will count $20.8 million against the Lions' salary cap this season, $19.3 million in 2014.

The Free Press reported that if the Lions can't get a deal done before the 2014 season, they risk exposing their franchise quarterback to free agency or being enforced to use a $23.2-million franchise tag to keep him away from other interested teams.

Several other big-name QBs received extensions this offseason. The Baltimore Ravens' Joe Flacco signed for $51 million guaranteed on a $120-million deal a month after winning the Super Bowl, the Dallas Cowboys' Tony Romo received $55 million guaranteed on a seven-year, $119-million deal, and the Green Bay Packers' Aaron Rodgers negotiated $54 million guaranteed on a $130-million deal.

The newspaper added that Stafford could command a contract similar to those quarterbacks.