Last season, Alexander, who was the team's second-leading receiver, had 37 catches for 658 yards and eight touchdowns. He was a consistent downfield threat, averaging 17.8 yards per reception. In the seven games he started in 2012, he had a touchdown reception in each game.
He went undrafted in 2010 primarily because of injury problems. He tore his left ACL three times while in college at Missouri, and the team was hoping he would emerge as Philip Rivers' top target.
The team gave Alexander a one-year, $1.323 million restricted free-agent tender in April.