Matt Cassel had until Friday to decide if he'd exercise the option for the second year of his contract with the Vikings. Darren Wolfson, 1500 ESPN contributor, first reported Wednesday that Cassel intended to void the second year. Now, Pro Football Talk's Mike Florio, citing a league source, reports Cassel has opted out. Cassel will become a free agent March 11, when NFL free agency opens. He may be the top available quarterback in free agency. The Vikings should look to re-sign Cassel, and new offensive coordinator said Thursday that quarterbacks coach Scott Turner has had positive discussions with Cassel. Florio suggested other landing spots as well, such as Atlanta (backup), Tampa Bay and Houston.