It'll be a next-men-up scenario for the Steelers' defense again on Sunday night in Buffalo.
The only question is, how many men?
The Steelers know they'll be without inside linebacker Devin Bush and outside linebacker Bud Dupree, whose 2020 seasons are over.
They also didn't have cornerback Steven Nelson available on Monday evening and then lost inside linebacker Robert Spillane and cornerback Joe Haden during what became a 23-17 loss to Washington.
The key to replacing however many players need to be replaced, in defensive coordinator Keith Butler's estimation, is the replacements knowing what they're supposed to be doing and then executing when called upon.
The Steelers will be expecting their fill-in starters and role players in an expanded role to execute fundamentals and be assignment sound more than they'll demand players such as outside linebacker Alex Highsmith or cornerback Cam Sutton to suddenly become All-Pros.
The Steelers prepare for the Week 14 matchup against the Buffalo Bills
"You'll probably hear me say this 100 times, the two things that get you beat on defense are mental mistakes and missed tackles," Butler emphasized today. "Mental mistakes means I drop a coverage or I'm not covering a guy or I'm not in the gap I'm supposed to be in the running game. And if you miss a tackle in the open field and they keep running down the field, that always hurts you.
"We gotta coach better, No. 1. No. 2, we gotta play better, also. We're all on the hook for it. We all wanna be good. We all wanna win a world championship. We're gonna try to do what it takes to do that, and that's trusting each other in terms of what we're supposed to be doing."
The on-field preparation for Buffalo began on Wednesday.
Nelson (knee) was a full participant in practice.
Spillane (knee) and Haden (concussion) didn't take part.
The impact of potential unavailabilities can be minimized, Butler believes, as long as those who are playing instead are up to speed with the schemes.
If they can be trusted with their responsibilities, the temptation will lessen for others to try to do too much and threaten the integrity of the defense.
"Our guys are pretty good in terms of knowing what the guys in front of them are doing and learning form that," Butler said. "Obviously, they haven't had as many reps as you'd want to have, but our guys are pretty smart. Most of the time they won't make mental errors."
Highsmith (started for Dupree), Sutton (started for Nelson) and inside linebacker Avery Williamson (replaced Spillane) all played more defensive snaps against Washington than they had previously this season for the Steelers.
"I've never worried about Alex," Butler said. "Like I said last week, you tell him one time and he's got it. You don't have to worry about him making mental mistakes or missed tackles. He did a good job for us. There's a couple things he can improve on but he's going to get better the more he plays."
Sutton "knows what everybody on the field is doing for the most part in most of the defenses that we're in if not all of them," Butler said. "Having Cam and people like him is always beneficial."
And Williamson is "picking it up" after arriving from the New York Jets in a trade.
"It seems like somebody was real timely with getting that trade, you know what I'm saying?" Butler noted.
"You never know how injuries are going to affect you or what's going on with COVID-19, those situations," Butler continued. "It's been a little bit tougher this year for us. So we gotta kinda be, as (head coach) Mike (Tomlin) says, light on our feet and be able to adjust and try to plan for things and make sure you have guys in there that can help you win.
"I think our guys want to do that, the guys that we've had to call on. It's time for us to step up, if we've been backups and stuff like that. If we can do that we'll be alright."