Seattle Seahawks starting tight end Zach Miller underwent surgery on his ankle during the bye week and is expected to miss two games, a source told ESPN.

The Seahawks announced only that Miller would be out for an undetermined amount of time.

Zach Miller caught 33 passes for 387 yards and five TDs during the Seahawks' march to the Super Bowl title last season. AP Photo/Rick Scuteri

"He had his ankle cleaned up. There's a lot of speculation about how long it's going to take," Carroll said Monday. "We'll just have to wait and see. We don't know yet. We'll give him a couple of weeks, then we'll go week to week and see how he does."

Miller, an eight-year veteran out of Arizona State, played the entire game against the Denver Broncos in Week 3. He was on the injury report that week and did not practice the Wednesday and Thursday before the game.

"It's been bothering him for a number of weeks. He's been playing with it and we don't want him to have to tolerate it any longer," Carroll said. "We wanted to fix him up and hope he has a speedy recovery. He had some loose bodies [in his ankle] and it was very uncomfortable."

Miller, 28, restructured his contract in the offseason to stay in Seattle, reducing his salary to $3 million a year plus $1 million in possible incentives.

The Seahawks currently have two other tight ends -- second-year player Luke Willson and Cooper Helfet, who was on the practice squad before making the 53-man roster this season. Helfet played his first NFL game against Denver on Sept. 21.