Vikings quarterback Matt Cassel officially opted out of the final year of his two-year contract today, Pro Football Talk reported, citing a league source.
Cassel signed a two-year, $7.4 million deal before last season to back up Christian Ponder. By the end of the season, Cassel was the team's starter.
By exploring the free agent market, Cassel stands to get a long term contract for more money. The Vikings could still re-sign him when free agency begins March. 8.