Posted by ESPN.com's Mike Sando
Biggest surprise: The 49ers kept only five receivers, a number that seemed low given injuries and the demands offensive coordinator Mike Martz places on the position. Veteran Ashley Lelie simply didn't do enough in the 49ers' eyes to justify keeping a sixth player at the position. Arnaz Battle, Isaac Bruce, Bryant Johnson, Josh Morgan and Jason Hill were the five keepers.
No-brainers: The 49ers did not release quarterback Alex Smith even though his future with the organization appears bleak at best. Cutting Smith might have brought an end to a painful chapter in 49ers history, but the team can't bet the season on unproven starter J.T. O'Sullivan. Smith provides a measure of insurance if O'Sullivan falters.
What's next: Expect the 49ers to monitor the situation at receiver closely. Johnson has returned to the lineup, but hamstring injuries can linger. Losing Johnson for any significant period of time could force the team to seek veteran help at the position.