Tuiasosopo signed a contract Thursday to return to the team that drafted him in the second round in 2001.
Tuiasosopo played sparingly as a backup for six seasons in Oakland before leaving to sign with the Jets as a free agent last season. He did not play in a single game with New York.
Tuiasosopo was dressed in street clothes at the Raiders' offseason practice on Thursday, consulting with quarterback coach John DeFilippo as the other QBs went through drills.
Russell, the No. 1 overall pick in the 2007 draft, will be the starter in Oakland this season, but Tuiasosopo will have a chance to compete with Walter as the second-stringer. Tuiasosopo has more mobility than Walter, which could make him better suited to run coach Lane Kiffin's offense.
Tuiasosopo completed 48 of 88 passes for 550 yards, two touchdowns and seven interceptions in his time with the Raiders. He threw only four passes in his first two seasons before getting a chance when Rich Gannon went down with an injury in 2003.
But he tore a knee ligament in his first start and did not play again until late in the 2005 season, when he was given one start in December against the New York Jets. He struggled in that game and Kerry Collins started the following week.
Tuiasosopo did not play the rest of that season and threw only 13 passes in his final year on Oakland, when the Raiders ran an offense under coach Art Shell that was not suited to his strengths.
Copyright 2008 by The Associated Press