Tim Duncan will sign a three-year contract with the Spurs this week, league sources told Yahoo! Sports.

Duncan’s representatives and the Spurs are finalizing a few items in the contract, but the structure has been agreed upon. The contract has a player option for the third season and is fully guaranteed. The deal also has a no-trade clause, sources said, and should take Duncan to the end of his playing days.

via Johnny Ludden of Yahoo! Sports