The Niners opened up the three-week practice window for Alexander to be activated from injured reserve in the playoffs. He has not been cleared yet for contact. Alexander was placed on IR after getting injured Oct. 31 in Arizona.
Coach Kyle Shanahan said earlier in the week that he was hopeful Alexander could return if the Niners make it to the NFC title game.
San Francisco (13-3) earned a first-round bye after capturing the top seed in the NFC playoffs. The Niners will host either Minnesota, Seattle or Philadelphia in the division round on Jan. 11.
Alexander was a key free agent signing for San Francisco last offseason and was one of the emotional leaders of the defense. He had 34 tackles, one forced fumble and one interception in eight games before getting hurt. He also excelled at pass coverage against running backs and linebackers.
Rookie Dre Greenlaw took over his place and made the key tackle at the goal line to preserve the division-clinching win over the Seahawks.
Safety Jaquiski Tartt also took part in practice Thursday as the Niners returned to the field for the first time since winning the NFC West title with a season-ending victory at Seattle on Sunday. Tartt missed the past four games with injured ribs.
Guard Mike Person also was practicing after missing the past two games with a neck injury.
Edge rusher Dee Ford was working on the side as he tries to make his way back from injuries to his hamstring and quadriceps.
Source: Fox Sports