Linebacker Fred Warner, who has not missed a game in his four-year NFL career, was on the 49ers' sideline for 22 snaps Sunday with a hamstring injury.
The 49ers' other top linebacker, Dre Greenlaw, was on the field for only 13 plays before he aggravated a groin injury and could not continue.
That shifted the main duties in the middle of the 49ers’ defense to Azeez Al-Shaair, a third-year player from Florida Atlantic.
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And Al-Shaair came through in a big way in the 49ers’ 34-26 victory over the Minnesota Vikings on Sunday at Levi’s Stadium.
“Our whole room is so close from top to bottom, so when you have both of them go out, obviously that's a huge hit and then you got Marcell (Harris) and Demetrius (Flannigan-Fowles) come in, and we just play off of each other and we just have each other's backs,” Al-Shaair said.
“It’s you keep chugging and keep going. Fred and Dre are right there on the sideline. We're all talking while communicating with the rest of the guys. You just see us all just play together, play for each other.”
Al-Shaair registered a team-high eight tackles while collecting a game-changing interception of Vikings quarterback Kirk Cousins. He also came up with a fumble recovery. He became the first 49ers player with an interception and fumble recovery in the same game since cornerback Perrish Cox in 2014.
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Al-Shaair took over the communication duties after Warner’s injury. He was entrusted with the role of receiving the play call from defensive coordinator DeMeco Ryans, then relaying it to his teammates in the huddle before every snap.
“Like Fred, when he has the mic in his helmet, he's communicating, we're all communicating,” Al-Shaair said. “So now it's obviously me. I might be giving the call, but it's the same thing. Now, the guys that I'm in with, they're communicating as well.
“And I think that's what helps when you have a really good defense is when you got multiple guys communicating the calls and helping get everything lined up.”
In addition to the increased responsibilities for Al-Shaair, the 49ers turned to Harris to play 17 snaps and Flannigan-Fowles was on the field for 11 plays.
Warner and Greenlaw were scheduled for MRI examinations on Monday to determine the extent of their injuries and set a tentative timetable for their returns.
Here is how much action every 49ers player saw on offense, defense and special teams.
Quarterback: Jimmy Garoppolo 70
Running back: Elijah Mitchell 49, Kyle Juszczyk 44, Jeff Wilson 10
Wide receiver: Brandon Aiyuk 63, Deebo Samuel 46, Jauan Jennings 26, Trent Sherfield 20, Travis Benjamin 3
Tight end: George Kittle 65, Charlie Woerner 19, Ross Dwelley 5
Offensive line: Laken Tomlinson 70, Daniel Brunskill 70, Tom Compton 70, Alex Mack 70, Trent Williams 70
Defensive line: Arik Armstead 48, Nick Bosa 44, Samson Ebukam 40, D.J. Jones 31, Arden Key 23, Charles Omenihu 15, Kevin Givens 13, Kentavius Street 5
Linebacker: Azeez Al-Shaair 48, Fred Warner 33, Marcell Harris 17, Dre Greenlaw 13, Demetrius Flannigan-Fowles 11
Cornerback: Josh Norman 55, Emmanuel Moseley 55, K’Waun Williams 31, Dontae Johnson 3
Safety: Jimmie Ward 55, Jaquiski Tartt 34, Talanoa Hufanga 31
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Special teams: Woerner 25, Harris 21, Flannigan-Fowles 21, Johnson 21, Trenton Cannon 18, Sherfield 18, Hufanga-Tartt 18, Mitch Wishnowsky 15, Ambry Thomas 13, Deommodore Lenoir 12, Dwelley 11, Taybor Pepper 10, Armstead 10, Jones 10, Robbie Gould 9, Tartt 9, Jake Brendel 7, Aaron Banks 7, Brunskill 7, Tomlinson 7, Compton 7, Wilson 5, Trey Sermon 4, Aiyuk 3, Juszczyk 3, Jennings 3, Ebukam 3, Key 3, Omenihu 3, Street 3, Al-Shaair 1, Ward 1
Did not play: QB Trey Lance, OL Jaylon Moore
Not active: RB JaMycal Hasty (ankle), OL Colton McKivitz, DL Maurice Hurst (calf), DE Jordan Willis