It was a change head coach Mike Tomlin had hinted was coming but also one free safety Minkah Fitzpatrick maintained wouldn't be made.
Defensive coordinator Keith Butler is ready for more of the same.
"We're gonna use his versatility," Butler confirmed prior to practice today.
Fitzpatrick's versatility was on display in Sunday's 23-16 victory over the Bills in a manner it hadn't been previously with the Steelers.
Not that moving from free safety to a box-safety-like/linebacker-hybrid-type position on the second level was new to Fitzpatrick.
"It was new for him last week," Butler said. "He did it at Alabama. We figured he could do it here, too.
"And he can."
Fitzpatrick did it 28 times in the Bills game.
Tre Norwood, a slot cornerback in the five-defensive backs "nickel," moved back to free safety to take Fitzpatrick's place when Fitzpatrick moved up in the six-defensive backs "dime."
"Troy (Polamalu) did the same thing," Butler said. "He moved around a little bit."
Fitzpatrick won't be afforded the same freedom of expression in his new role Polamalu was when it came to playing on instincts or hunches.
"Not as much," Butler said. "Not yet."
The Steelers played "nickel" for 47 snaps and "dime" 28 times in Buffalo.
Their base defense was deployed on four occasions.
It was all a part of a division of labor that included Norwood and Arthur Maulet taking snaps at slot cornerback in the "nickel," Joe Schobert and Devin Bush sharing the role as the lone inside linebacker in the "dime," and outside cornerback Cam Sutton moving to the inside position he'd traditionally occupied in the "dime." When Sutton moved inside, cornerback James Pierre took over outside.
Tomlin had revealed such intentions for Fitzpatrick when he appeared on a podcast with Peter Schrager of the NFL Network prior to the beginning of training camp.
"We're in the process right now this summer of talking about dealing with his alignment depth based on the nature of the offenses, conversations, quite honestly, that you could not have with most guys," Tomlin said then.
Fitzpatrick isn't most guys.
But he repeatedly insisted the status quo would be observed as it related to where he'd be lining up heading into the season, including on the Thursday before the Bills game.
"I don't think too much is going to change from what we saw last year," Fitzpatrick said. "Playing in the middle of the field, playing in the post occasionally, coming down and playing my 'robber' technique.
"Like I said earlier in camp, if it's not broken don't change it. It's been working the past two years so keep it the same."
Except the Steelers didn't.
"Most quarterbacks read the safeties in terms of dissecting defenses," Butler said. "As much as you can move him around, as much as you can play different positions with him, that's going to give them problems."
Fitzpatrick's biggest play against the Bills might have been made from free safety.
His ability to read, react and ultimately tackle running back Matt Breida 1 yard shy of the line to gain on third-and-3 from the Steelers 43-yard line resulted in the Bills going for the first down on fourth-and-1 on a play that was ultimately blown up by Sutton.
"Minkah came down like a missile from the middle of the field," outside linebacker T.J. Watt said on Sunday.
"Another Troy-like deal," Butler added today.
There was nothing new about that.