Staley signs extension with Niners

The San Francisco 49ers signed tackle Joe Staley to a six-year contract extension through 2017, the team announced Thursday.

Staley will receive $42 million for the six additional years and the new money could grow to $45 million depending on how he plays, a source told ESPN.com. Staley is expected to receive $18 million in guarantees.

The unusual part of this deal is that the team did it after Staley's first two seasons. Normally, a team wants its draft choice to play out most of his rookie contract. The 49ers felt so good about Staley's future that they decided to do the deal now and lock him up for the future.

"Joe Staley is the type of player we want to continue to add to this football team," general manager Scot McCloughan said. "He's a tough, versatile, no-nonsense type of guy who wants to do whatever it takes to help his team win football games. Joe is a consummate team player and has been completely unselfish in the way he has approached his role on this team. We know what he means to the success of the 49ers and getting this extension done puts us in a very nice position for the future."

Staley was the 28th pick in the 2007 draft. He has started 32 games.

John Clayton is a senior NFL writer for ESPN.com.