After dominating against San Francisco, inside linebacker Ryan Shazier will be a spectator when the Steelers face St. Louis.
Shazier (shoulder) missed his third straight day of practice today in the wake of collecting 15 tackles, a sack, a forced fumble and a fumble recovery in the Steelers' 43-18 triumph over the 49ers.
He has been declared out for Sunday's meeting with the Rams in the Edward Jones Dome.
"He's a special athlete, lotta speed out there, lotta energy," fellow inside linebacker Lawrence Timmons said of Shazier. "He's going to be missed, that's for sure. But we have capable guys to come in and do the job and hold on until he gets back, gets healthy.
"We're going to be fine. I just hope he comes back fast because we need him. He's one of our best players right now. But Vince Williams, veteran guy, he's been on the team for a while. (Sean) Spence has been on the team for a while so those guys have reps so they're going to be fine.
"I'm helping with the cause out there, get 'em lined up and just playing ball."
Williams, a third-year pro, started three games last season and 11 as a rookie in 2013 when he filled after Larry Foote was lost for the season in the opener.
Spence, a fourth-year pro, started eight times last season, his first back on the field after suffering a potentially career-ending knee injury as a rookie in August of 2012.
The two shared the position next to Timmons last season when Shazier was either injured or not occupying the top spot on the depth chart.
Shazier started five of the nine games he appeared in as a rookie in 2014 but none after a Nov. 2 win over Baltimore.
"I was the run-down guy; (Williams) was the pass-(down) guy," Spence recalled of how the Steelers lined up minus Shazier last season. "It went well. I think we feed off each other great. I think it was great for the defense. I think the coaches just liked it that way. They thought it was a good fit and we went with it.
"However the coaches see fit, that's how we're going to do it. We'll be prepared for whatever the coaches throw at us."
Williams declared himself "very prepared" to help pick up the slack in Shazier's absence after "a great week of practice.
"I'm just ready to go out there and play," he said. "I think I'm going to play, I'm pretty sure I'm going to play. Me and Spence have been taking the majority of the reps. I'm just going to pray for Ryan and hope he heals up fast."
"When my number gets called I'm ready to play football. When (defensive coordinator Keith Butler) calls for No. 98 he's going to be ready to go."
Shazier's afternoon against San Francisco included three tackles for a loss and a quarterback hit. Of his 15 total tackles, 11 were solo.
"He had one of the best games of his career," Timmons said. "I feel sorry for him but that's the NFL. I'm sure he's going to respond properly once he's healthy and have a great year."
Added Spence: "He wants to be out there. He wants to be playing. Sometimes injuries just happen. I'm a guy who's been through it and I understand where he's coming from. I just told him to keep his head up and he'll be back out there before you know it."
OUT: Shazier, NT Daniel McCullers (knee).
QUESTIONABLE: CB Cortez Allen (knee).
PROBABLE: CB William Gay (not injury related), WR Markus Wheaton (chest), DE Cam Heyward (elbow).