Inside linebacker Michael Wilhoite, who started 28 games over the past two seasons, has not played a snap of defense in the 49ers' first two games.
But Wilhoite moved a step closer to getting on the field as a contributor on defense after Ray-Ray Armstrong was lost for the season due a torn pectoral. Armstrong was used primarily for his coverage skills in passing situations to complement starter Gerald Hodges.
The 49ers return to action Sunday against the Seattle Seahawks, and it's unclear exactly how the team will compensate for the loss of Armstrong. It could mean more playing time for Hodges and backup safety Jaquiski Tartt. It could mean Wilhoite takes the field on defense for the first time in a specialized role.
"I've said all along that we're going to need Wilhoite, we're going to need Gerald to help us win football games and those guys will step up and they'll do a great job in that role," 49ers defensive coordinator Jim O'Neil said.
"I know for me, I just got to be prepared when I'm called on, just like I've been the past four years, and be a good special-teams player," Wilhoite said.
Wilhoite's spot on the 49ers' 53-man roster appeared particularly tenuous when he played every defensive snap in the team's exhibition finale. Typically, the players who see the most action in the final preseason game are among the first to be informed they did not make it past the final cuts.
San Francisco 49ers
Wilhoite said he tried to use the extensive playing time to prepare himself for a situation he might face in the future – either with the 49ers or with another team.
"I knew I had to go out there and play," Wilhoite said. "There's no other way to approach than you go out there and you play 60 minutes and you hope that prepares you for another situation, maybe further down the road."
Wilhoite said he has remains ready for anything the coaching staff asks of him. In the first two games, Wilhoite has played 56 plays on special teams, while remaining ready to play defense, if needed. After Armstrong's injury against the Panthers, Hodges picked up the slack by playing more on defense and more on special teams.
"I instantly thought of Gerald this weekend," Wilhoite said. "He was playing special teams. If it were me in that situation, I've been through it. At least I'd know what to do.
"In the NFL, 16 games is a long season. You've seen some of the greats go down at any point in time. I think everybody, no matter if you're a three or a two, you have to stay prepared. "
