JaMarcus Russell hasn't turned the ball over in two preseason appearances for Oakland. (Jed Jacobsohn/Getty Images)

The Oakland Raiders parted ways with JaMarcus Russell on Thursday, releasing the former No. 1 overall draft pick after just three seasons.

Senior executive John Herrera confirmed the move to The Associated Press, stating, "we wish him well."

The move was believed to be a foregone conclusion after the Raiders acquired Washington quarterback Jason Campbell in a trade nearly two weeks ago.

Russell was selected first overall in the 2007 NFL draft by Oakland after a collegiate career in which he compiled a 25-4 mark with the LSU Tigers. The Raiders coveted the six-foot-three pivot for his arm strength and size.

The problems began almost immediately. He saw limited action in his first season after a contract holdout that lasted until September, signing a six-year, $61 million US deal that guaranteed him $31 million.

Russell showed promise in 2008, throwing 13 touchdowns and eight interceptions, but regressed the next year.

The quarterback's weight ballooned to close to 300 pounds and many questioned his maturity and dedication to learning the playbook.

Longtime NFL quarterback Jeff Garcia, who spent time with the Raiders, questioned his ability to provide leadership in the huddle, echoing concerns that Raiders coach Lane Kiffin had before he was fired in a bitter row by Oakland owner Al Davis.

"[Russell] is a great player. Get over it and coach this team on the field," Davis read from a letter he sent Kiffin before the firing. "That is what you were hired to do. We can win with this team."

Russell was replaced as starter in 2009 by journeyman Bruce Gradkowski after throwing for just three touchdowns in 12 appearances, with 11 interceptions and a lowly 48.8 completion percentage.

Overall, Russell went 7-18 as a starter and lost 15 fumbles.

The Raiders paid Russell, still just 24, more than $36 million through last season. They still owe him $3 million more but saved $6.45 million by not having him on the roster in 2010.

Russell was the first of three consecutive Oakland first-round draft picks who have yet to live up to their potential. Running back Darren McFadden has battled injuries and gained just 856 rushing yards in two seasons, while wide receiver Darrius Heyward-Bey caught just nine passes in his 2009 rookie campaign.

With files from The Associated Press