ASHBURN, Va. (AP) A veteran of more than 50 starts in his first four NFL seasons, linebacker Mason Foster spent most of September as a free agent. He was in limbo, sleeping on the futon of his college roommate and best friend, an assistant strength and conditioning coach at the University of South Dakota.
Foster was waiting for a phone call from a team. He had been cut by the Bears about a week before the start of the regular season; a couple of days later, a cousin helped load up a truck and make the 7-hour drive from Chicago to Vermillion, South Dakota.
''I was confident the opportunity would come. But it's tough. You're just sitting there. I sat there for weeks, watching games,'' Foster said. ''My friend wrote up a workout plan for me and let me stay on his couch and we just worked out the whole time. I wanted to play meaningful games and help a team. And it's all happening.''
Late in September, he got that call - from the Washington Redskins, who signed him after a tryout. And now Foster is a starting middle linebacker for the NFC East champions as they enter the playoffs, hosting the Green Bay Packers on Sunday.
His story is not unique. For all of the time and money teams invest in trying to figure out which college players to draft or which big-name free agents to add in the offseason, sometimes key playoff contributions come from guys who arrive ''off the street,'' in the league's lingo.
A year ago, for example, Chris Matthews got cut at the end of training camp by Seattle and was available to anyone in need of a receiver. Eventually, Matthews made his way back to the Seahawks and made a mark down the stretch, recovering an onside kick in the NFC championship game, then catching four passes for 109 yards and a touchdown in the Super Bowl.
Scan the rosters of the 12 postseason teams, and there are plenty of players brought in late, often because of injuries that prompted a GM to seek help.
The NFC's No. 1 seed, Carolina, picked up starting cornerback Robert McClain and nickel back Cortland Finnegan after Charles Tillman and Bene Benwikere were sidelined.
''They're veterans, and that's the biggest thing,'' Panthers coach Ron Rivera said. ''If we were talking about playing two straight-off-the-street rookies, yeah, there would be some concern.''
Shiloh Keo - signed by Denver after he made a Twitter plea - filled in because of four injured safeties and made a late interception in a Week 17 victory that clinched the AFC's No. 1 seed for the Broncos.
''He's a great example of: If you think you can play, hang in there,'' said Denver coach Gary Kubiak, whose team signed offensive lineman Tyler Columbus about 48 hours after he was released by Atlanta.
After losing running backs Dion James and LeGarrette Blount - himself a street free agent last season - to injuries, New England brought in Steven Jackson, who initially told coach Bill Belichick he didn't think he was in good enough shape. Pittsburgh added Chris Boswell in early October, its fourth kicker of the season, and all he did was go 29 of 32 on field-goal attempts and 26 of 27 on extra points. Houston used a pair of midseason pickups at quarterback on the way to an AFC South title, Brandon Weeden and T.J. Yates.
Arizona, the NFC's No. 2 seed, added pass rusher extraordinaire Dwight Freeney, safety D.J. Swearinger and defensive tackle Red Bryant along the way.
Freeney was close to retiring for good when the Cardinals called in mid-October after the team's best outside rusher was injured; by December, he was earning $100,000 in incentive pay per sack.
''Two months ago, I didn't know if I was going to play,'' Freeney said. ''But the things we're going through now is why I decided to come back.''
In addition to Foster, the Redskins signed another starter, cornerback Will Blackmon, a ninth-year veteran released by Jacksonville. Third-down back Pierre Thomas and kicker Dustin Hopkins came in ''off the street,'' too. Reserve cornerback Cary Williams was signed just last week for depth. Those types of resourceful moves are part of why general manager Scot McCloughan is being lauded as one of this season's top executives.
That's not to say it always works out for player and team, of course.
Last season, Pittsburgh signed running back Ben Tate for the playoffs after Le'Veon Bell hurt his knee. Tate fumbled and gained only 19 yards in the Steelers' wild-card loss.
There can be reasons other than financial ones why a player's former team decided to let him go and no one else signed him. Plus, a new acquisition needs to learn a system and playbook without training camp or exhibition games.
''There's a lot of onus on us to get ready ourselves,'' Washington's Blackmon said. ''Scot brought in guys who are professional, who are veterans who have played a lot of football, so he doesn't have to worry about if they're going to be ready.''
AP Pro Football Writers Dave Campbell and Arnie Stapleton, and AP Sports Writers Genaro Armas, Bob Baum, Tim Booth, Jimmy Golen, Will Graves, Joe Kay, Steve Reed, Kristie Rieken and Dave Skretta contributed to this report.
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