49ers' All-Pro linebacker NaVorro Bowman back on practice field (w/video)

SANTA CLARA - San Francisco 49ers linebacker NaVorro Bowman was scheduled for his first practice of the season Tuesday, officially opening a 21-day window during which the team can decide whether to activate him or send him to the injured reserve list.

The three-time All-Pro sustained a major injury to his left knee in last season’s NFC championship game against the Seattle Seahawks. But he has been a constant presence at the 49ers training facility and has been engaging with his teammates as though preparing for every game.

“He’s looked good to me the past two weeks,” linebacker Michael Wilhoite said. “I don’t know what his work load will be but I’m excited about having him back.”

San Francisco will maintain a cautious approach with Bowman as he eases his way back into football shape. Coach Jim Harbaugh had said Monday that he expects Bowman will “take advantage of some walkthrough, some limited individual drills.”

Bowman had appeared in every game the 49ers played over the previous four years and had started 58, including the playoffs. He had a spectacular season in 2013, with 145 tackles, including career highs in solo tackles (120), passes defended (8) and sacks (5).

He also recorded his only career touchdown on an 89-yard interception return against the Atlanta Falcons.

“I’m sure he’s chomping at the bit,” Wilhoite said. “But at the same time he has to take care of his body. We’re ready to have him around 100 percent of the time.”