SANTA CLARA Wide receiver Michael Crabtree joined his 49ers teammates at practice Tuesday for the first time since tearing his right Achilles' tendon May 21.
Crabtree's clearance for practice triggered a 21-day window for adding him to the 53-man roster, which could put him back on the field for the team's Dec. 1 game against the Rams and, perhaps more significant, give him a warmup for the following week's rematch with the Seahawks.
Crabtree completely tore the tendon during a spring organized team activity session and started the season on the physically-unable-to-perform list. The 49ers had until Nov. 19 to clear him for practice, but they felt he had made enough progress to do so two weeks early.
Today marks 24 weeks since Crabtree suffered the injury, which in the past required at least a year of rehabilitation but one from which players recently have been able to return in six months.
The 49ers' passing offense is last in the NFL, averaging 190 yards per game, largely because they have raced to large first-half leads in recent weeks and have one of the top-ranked rushing offenses (153 yards a game). But the 49ers also could use help at wide receiver, a position at which no other player aside from Anquan Boldin has made an impact.
Monday, the 49ers activated one previously injured receiver, Mario Manningham. Now it seems as if they could get their top wideout, Crabtree, back in time for the pivotal Dec. 8 showdown with division-leading Seattle. The Seahawks, who have not had their bye yet, lead the 49ers by 1 1/2 games.
Crabtree has looked sharp working out with trainers and strength coaches. Now he'll work on rebuilding his confidence.
"When you're a running back or a receiver, you've got to stick that foot in the dirt," general manager Trent Baalke said. "And you've got to do it at the velocity these guys have to do it at now the mind starts playing with you. So getting that confidence back (is critical)."
Crabtree also will work on re-establishing his rapport with quarterback Colin Kaepernick. They had great chemistry in Kaepernick's 10 starts last season, with Crabtree catching 61 passes for 880 yards and eight touchdowns.
Crabtree finished the regular season with 1,105 receiving yards and became the first 49ers receiver to surpass 1,000 yards since Terrell Owens in 2003.
Asomugha free Veteran cornerback Nnamdi Asomugha, who was released Monday by the 49ers, passed through waivers without any teams claiming him. That makes Asomugha, 32, a free agent. It also means the 49ers now owe him his full $1.35 million salary.