With an eye toward the future, and the continued security of quarterback Brett Favre, the Green Bay Packers have extended the contract of starting center Mike Flanagan, a move that keeps the sixth-year veteran off the free-agent market next spring.

Flanagan, 27, signed a four-year extension through the 2005 season. Without the contract, he would have been eligible for unrestricted free agency at the end of this season, and he would have drawn considerable interest in the market.

The extension is worth approximately $10 million and ESPN.com confirmed it includes a $2.5 million signing bonus. The base salaries are $660,000 (2002), $1.558 million (2003), $1.758 million (2004) and $1.908 million (2005), according to NFL Players Association contract documents. By completing the deal before next Monday, the Packers can count a portion of the signing bonus as salary for the 2001 season.

In addition to securing the services of a center whom the Packers feel has a bright future, the deal further solidifies the team's offensive line unit. With the exception of left guard Mike Wahle, who can become a free agent next spring, all of the other Green Bay starting linemen are under contract now through at least the 2003 season.

The retention of Flanagan, who is in his first season as a full-time starter but who has been playing at a Pro Bowl level, was a key for the Packers. The club has several pending free agents and keeping Flanagan was a high priority for team officials.

A former UCLA standout and a third-round choice in the 1996 draft, Flanagan has been a notable example of perseverance. He broke his right leg in his rookie training camp and the injury essentially sidelined him for two full seasons. He finally played in a regular season game in 1998, his third year in the league. Entering this season, he had appeared in just 33 games and started two of them.

But the Packers staff knew Flanagan had great potential, and stuck with him, and he won the starting job over veteran Frank Winters in training camp.

Len Pasquarelli is a senior NFL writer for ESPN.com.