ORCHARD PARK, N.Y. — Fred Jackson never gave up on his pursuit to make it in the NFL, and now the Buffalo Bills running back has the lengthy contract to prove it.

Jackson signed a four-year contract extension on Wednesday as both a reward for his perseverance and his ability to provide the Bills' run game a valuable one-two punch behind starter Marshawn Lynch. It's a particularly significant deal for someone who played at Division III Coe College, spent a few years playing in the U.S. Indoor Football League before finally breaking into the NFL on Buffalo's practice squad in 2006.

"I traveled a road that not a lot of people take or will take," Jackson said. "I'm happy that I took the road, because I'm appreciative for being here and being able to have had the success that I have had."

Though the financial details of the contract were not immediately available, the extension is considered far superior than the one-year $460,000 tender the Bills offered Jackson to retain his rights this offseason. Jackson declined the offer in a bid to negotiate a long-term deal, and was pleased with the results.

"It let's me know where I stand with the team," Jackson said. "I thought it would be done a lot sooner than it actually was. It wasn't, but we're here now. I could just focus on playing football now."

He's coming off a solid second season with the Bills, in which he had 888 yards from scrimmage — including 571 yards rushing — with three touchdowns in 16 games, including three starts. Jackson's stock rose during his rookie season in 2007, when he supplanted rookie fourth-round pick Dwayne Wright as the team's backup.

Jackson's performance led to the team releasing Wright the following offseason.

Jackson will get the opportunity to do even more as he'll compete with newly signed veteran free agent Dominic Rhodes to start this season in place of Lynch, who'll miss the first three games while serving an NFL suspension.

"I'm excited about it and looking forward to the opportunity," Jackson said, while noting he'd prefer Lynch wasn't suspended. "I'm heading into the season knowing that I'm going to be the guy that they're going to be leaning on."

Free agent linebacker Pisa Tinoisamoa was scheduled to visit with the Bills on Wednesday, but the team had no update on whether he had arrived in Buffalo. A six-year NFL player, Tinoisamoa was released by the Rams in a surprising move last week, as he had led the team with 135 tackles last season.

The Bills are in the market to improve their linebacking corps to play alongside returning starters Paul Posluszny and Kawika Mitchell.