Two hours before the Ravens kicked off against the Los Angeles Chargers in Week 12, linebacker Roquan Smith was on the field wearing black shorts and a cutoff T-shirt testing the integrity of his hamstring injury with slim hopes he might still be able to play.

His backup, Malik Harrison, had been preparing all week as if he were the starting middle linebacker. And Chris Board, a seven-year veteran with three career starts, studied film like that Monday night might be his fourth.

Smith was ruled out, opening the door for Harrison and Board to take over the middle of the defense. Something clicked. The Ravens are now using those two and Trenton Simpson in a rotating platoon at linebacker, shoring up a soft spot on a unit that struggled mightily the first 10 weeks of the season but has since turned a corner.

“It’s been kinda crazy, honestly, just with the changing roles,” Board said. “But that’s kind of how the league works. You never know how things will shake out.”

Before Week 12, Board had spent most of his time with special teams. He had 11 total defensive snaps in 11 weeks. He’s averaging 31.6 in the three games since. And Harrison jumped from 90 total defensive snaps in 11 weeks, only going over 15 once, to 44.5 on average.

“They’re making the most of it,” coach John Harbaugh said.

Entering that game against the Chargers, the Ravens were still ranked last in passing defense. Since Week 11, they’ve given up the NFL’s fewest net yards per game (269) and rank atop the league in third-down defense.

Smith praised Harrison’s physicality. “The guy will knock your face mask off; it’s pretty crazy,” he said. Even running back Derrick Henry noticed, saying after the win at SoFi Stadium that there were a few hits where “everybody in the crowd went, ‘Oh.’”

Harrison stepped into the starting post against Los Angeles. After the Chargers scored handily on the opening drive, he shook off some jitters and had a career day with a team-high 13 tackles.

“They go down there the first drive, and we’re trying to figure out what’s going on and how we’re going to play these different things and talked through it, and he didn’t flinch for one second,” Harbaugh said. “I couldn’t be more proud of him.”

Against the Giants on Sunday, Harrison played a season-high 79% of defensive snaps and again finished with a team-high eight tackles and a sack. It’s thanks to the evolution of how he prepares during the week.

Harrison said he leans on veterans for advice. He’ll text Smith with film questions. Early in his career, there were days he’d practice just to practice. Now, and particularly these last few weeks, Harrison said he treats every day as if he’ll be the most important piece on the chess board come Sunday. “I just prepared my [butt] off all week,” he said. And some of his note-taking style is inspired by the veteran in a similar position.

“Chris Board has always been a guy where he’ll get zero reps,” Harrison said, “then you put him somewhere and he’s gonna do it right.”

Since taking a larger load on defense the past three games, Board logged 14 tackles and one for loss. That’s the best stretch of his career since 2021. Harbaugh called him an “underrated guy” with a knack for making plays on passing downs. “Heck, maybe we should have had him out there a little bit sooner,” Harbaugh said last month.

Nonetheless, he was ready when the time came.

“Snap-wise, it’s a toll on your body to play more,” Board said, “but mentally, I’ve been preparing for whenever this moment would come.”

Defensive coordinator Zach Orr can relate. The former Ravens linebacker knew he was far down the depth chart as a rookie, “which was fine,” he said. “Honestly, I wasn’t ready.” He learned how to prepare for when the moment finally arrived and made the most of it: Week 13 in 2016 against the Jacksonville Jaguars, sealing the win with an interception in the final seconds.

It’s the second mid-to-late season defensive shuffle Orr has pushed his chips in on and seen an immediate return.

Baltimore’s secondary rotated options next to their All-Pro safety, Kyle Hamilton, until finding a key that fit with Ar’Darius Washington. At linebacker, Simpson was handling duties with Smith, a two-time All-Pro, before Orr conversely leaned into the linebacker platoon on the heels of Smith’s injury. The reason it’s worked is Harrison and Board — two more names Pittsburgh will have on its scouting report whio weren’t there when they played on Nov. 17.

“They’re about as different as you can get defensively over the course of a month,” Steelers coach Mike Tomlin said, days out from traveling to Baltimore for a highly anticipated AFC North matchup Saturday.

Consider the age-old cliche: “Get ready so you don’t have to stay ready.” It’s been around as long as backups have had microphones pushed in front of their faces. Teammates say Harrison and Board embody it.

“I think those guys are perfect examples of everybody, like, ‘I’m just doing what’s best for the team, and then when my number is called, and I get my opportunity to play more, I’m gonna go out there and play good football,’” Orr said. “And both of those guys are playing good football for us. We’re happy, but it’s not [anything] we’re surprised by, by any means.”

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