SANTA CLARA -- Wide receiver Brandon Carswell has a torn anterior cruciate ligament in his right knee, an injury he suffered Wednesday not long after beginning his first practice with the 49ers.
Carswell, a Milpitas High and USC product, was signed to a two-year deal Wednesday after the 49ers released tight end Cameron Morrah.
"It was a real kick in the gut," 49ers coach Jim Harbaugh said of the injury.
The 49ers responded by bringing in former Indianapolis Colts receiver Austin Collie for a workout Thursday. He missed most of last season with a knee injury and also has a history of concussions.
"He was good," Harbaugh said of Collie's workout. "He had a patellar tear 7 ½ months ago and he's very far along. Pretty impressive." Collie caught more than 50 passes in each of his first three seasons, including a 2010 campaign cut short by concussion. He had 58 catches for 649 yards and eight touchdowns despite playing in only nine games that season.
Harbaugh, who indicated the 49ers would want to sign a receiver before training camp begins, said the team is still evaluating Collie.
"It's still ongoing," he said. "There's still a few more things we want to have checked out."
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