Linebacker Dre Greenlaw on Sunday looked like a player who wanted to cram a full season of aggression into one game.
And 49ers coach Kyle Shanahan loved it.
Well, he loved most of it, anyway.
Greenlaw opened the season in grand style with an interception return for a touchdown against the Detroit Lions in the 49ers' Week 1 victory.
But he sustained an injury that forced him to undergo core muscle surgery. He was out of action for 2 1/2 months. Then, Greenlaw aggravated his groin when he returned to the lineup in Week 12 against the Minnesota Vikings.
He appeared extra excited to be back on the field for the 49ers’ do-or-die Week 18 game against the Los Angeles Rams.
“I thought him playing out there was like watching Mike Tyson in that uniform,” 49ers coach Kyle Shanahan said, noting that he believes Greenlaw bears a resemblance to the former heavyweight champion.
It is a comparison linebacker Fred Warner said he has heard Shanahan make for the way Greenlaw will try to violently punch the ball away from offensive players.
Greenlaw was all over the place against the Rams with 12 tackles and a quarterback hit that forced a key Matthew Stafford incomplete pass on a third down. But Greenlaw was also penalized for unnecessary roughness and picked up a facemask penalty.
“He was so in the zone,” Shanahan said. “Honestly, if I was a fan, I probably would’ve been wearing his jersey in the stands that day because he plays the way I love to watch.
“We got to be careful with that. He did get a couple of personal fouls, and it’s a very fine line. But when you can play with that aggressiveness, that energy, the guy hasn’t played all year, and you can see how much he likes playing football.”
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Greenlaw was on the field for 63 of the 49ers’ 65 defensive plays against the Rams. His return to the lineup is a huge boost for the 49ers, who face the top-ranked Dallas Cowboys’ offense in the first round of the NFC playoffs on Sunday.
“We didn’t know how much he’d be able to go, and he went pretty much every play,” Shanahan said. “And you could see it in his eyes and the way he looks in his eyes are the way his actions are on the field. He’s very inspiring to us as coaches and players. I feel like he inspires our fans, too.
“So having Dre out there is a huge difference. And we really enjoyed it.”