He was drafted by the Dallas Cowboys in the sixth round of the 2008 NFL Draft after playing college football at Middle Tennessee State. Walden would also make journeys with the Kansas City Chiefs and Miami Dolphins before being signed by the Packers during the 2010 season. In the final season of the 2010 regular season, Walden was named NFC Defensive Player of the Week in only his second career start.
Walden was drafted by the Dallas Cowboys during the 2008 NFL Draft in the sixth round with the 167th overall pick. He signed a four-year contract with the Cowboys on July 22, 2008. However, he was waived by the team on August 30 during final cuts.
A day after being let go by the Cowboys, hoping he would clear waivers enabling them to sign him to their practice squad, Walden was claimed off waivers by the Kansas City Chiefs on August 31, 2008. Walden would play in nine games and contribute 10 tackles with the team. On November 19, the Chiefs waived Walden.
A day after being let go by the Chiefs, Walden was claimed off waivers the next day again, this time by the Miami Dolphins on November 20, 2008. It would be the third team Walden had played for during his rookie season. In six games, he contributed five total tackles.
During the 2009 season, Walden played 11 games for nine total tackles. In 2010, he was active for two games with Miami until being released.
After a onslaught of injuries to the Packers linebackers corps (which included Nick Barnett, Brad Jones, and Brady Poppinga being placed on injured reserve), Walden was signed off the street by the Packers on October 31, 2010. After Frank Zombo was sidelined by an injury, Walden was thrust in as a starter. In a win-or-go-home scenario in Week 17 against the Chicago Bears, Walden's second career start was the best game of his career on January 2, 2011. Walden led the team with 3 sacks and 12 tackles and was named NFC Defensive Player of the Week. He finished the season with twenty tackles in 9 games (two starts).