SANTA CLARA, Calif. -- The San Francisco 49ers' and linebacker NaVorro Bowman's worst fears were confirmed Monday morning when an MRI revealed that Bowman does indeed have a ruptured left Achilles tendon.
The Niners announced Monday afternoon that Bowman's injury is season-ending. He suffered the injury in a noncontact situation with about six minutes, 10 seconds left in the third quarter of Sunday's 24-17 loss to the Dallas Cowboys.
After falling to the ground in obvious pain, Bowman immediately clutched at his left leg and ankle. San Francisco medical personnel helped Bowman off the field and to the sideline, where he attempted to test the leg. After a few minutes, a cart brought Bowman to the locker room for further examinations.
The initial belief was that Bowman had a significant Achilles injury, which became official Monday morning.
"I mean, that's a hell of a loss," outside linebacker Aaron Lynch said. "We hope he comes back healthy, takes as long as he needs to take. But he was one of the leaders of our defense. Everybody knows who NaVorro Bowman is, so he's always one of the guys on the field that they game plan to -- so losing him on the defense, it's horrible. As far as our mindset, it's not going to change. We're going to miss him, but now we've got to just go play for him."
The Niners haven't officially placed Bowman on injured reserve, but that is the expected move to create room for Lynch, who is returning from a four-game suspension for violation of the league's policy on substance abuse. Lynch returned to practice under league exemption on Monday.
Meanwhile, the 49ers began preparations for Thursday night's game against Arizona and life after Bowman with a lengthy walk-through. Nick Bellore, who replaced Bowman against the Cowboys, said he'll be the starter in Bowman's stead against the Cardinals, "as far as I know."
Bellore, who has mostly played special teams in his five-plus seasons, was disappointed in the circumstances of how he's getting a chance to play defense but knows he steps into big shoes.
"I don't think you ever can (replace Bowman)," Bellore said. "Obviously, we'll have to rally together -- things will be different maybe defensively. We just have to kind of overcome him not being in there and we just have to step up. It's time for guys like myself and the linebacking room as a whole to step up."
As for Bowman, 28, it's off to what figures to be another lengthy rehabilitation. He is on his second major injury to his left leg in a span of 987 days. He suffered a torn ACL and MCL in his left knee in the NFC Championship Game after the 2013 season and then missed the entire 2014 season before returning last year and earning All-Pro honors for his league-leading 154 tackles.
The Niners signed Bowman in August to a four-year contract extension through the 2022 season.
"It's tough news hearing that about Bow," Bellore said. "He's a leader in this locker room and more importantly on the field. He's someone we all look up to; he's a fighter. He'll be back from this, but we all have to be ready to step in in the meantime."
49ers LB NaVorro Bowman to miss rest of season with Achilles injury