The Chiefs today released former starting quarterback Matt Cassel.

His departure from the Chiefs became imminent this week when they completed the trade with San Francisco for new starter Alex Smith and signed Smith’s backup, Chase Daniel, as a free agent.

The Chiefs tried to trade Cassel, but the task was difficult given Cassel’s 2013 salary of $7.5 million. His departure clears about $6 million of salary cap room.

Cassel came to the Chiefs in 2009 as the first player move under the new football administration of general manager Scott Pioli and coach Todd Haley. Cassel and Pioli had previously worked together with the New England Patriots, and Pioli saw Cassel as the young quarterback the Chiefs could build around.