The 49ers also signed running back Thomas Clayton from the practice squad to the active roster, another indication star running back Frank Gore probably won't play Sunday at Miami. Coach Mike Singletary said Gore's availability would be a game-day decision.

Gore, who's fifth in the NFL in total yards from scrimmage, sprained his left ankle while straining for a first down early in the second half of San Francisco's victory over the New York Jets.

The Miami native and former University of Miami star had been looking forward to facing the Dolphins for months, but he didn't participate in practice this week.

Battle, a six-year NFL veteran, played in just nine games this season, catching 24 passes for 318 yards while struggling with injuries. He returned to the 49ers' lineup last week against the Jets after missing four games, but aggravated his foot injury.

Second-year pro Jason Hill has filled in well for Battle.

Clayton has spent both of his NFL seasons on the 49ers' practice squad after the club drafted him in the sixth round out of Kansas State. He has performed well in the preseason twice, but couldn't win a spot on San Francisco's roster.