Updated

The Kansas City Chiefs did the expected on Thursday and released quarterback Matt Cassel.

After acquiring Alex Smith in a trade with San Francisco and signing Chase Daniel as a backup in the first couple days of free agency, Cassel was expected to go.

Cassel joined the Chiefs in July 2009 after leading New England to 11 wins while Tom Brady missed the 2008 season with a knee injury. After the Chiefs struggled in Cassel's first year, he helped the club to a surprise AFC West title in 2010.

The 30-year-old USC product played just 18 games over the past two seasons because of injuries and ineffectiveness. He suffered a concussion in early October this past season and played just nine games, throwing for 1,796 yards with six touchdowns and 12 interceptions.

Cassel completed 57.4 percent of his passes for 9,549 yards with 59 touchdowns and 44 interceptions during his four seasons in Kansas City. His 2010 campaign included 3,116 yards with 27 touchdowns and just seven picks.

A seventh-round pick of the Patriots in 2005, Cassel had thrown just 39 passes in his first three seasons as Brady's backup before being thrust into the starter's role in the 2008 season opener. He went on to throw for 3,693 yards with 21 touchdowns and 11 interceptions that season.