The rookie handled it well, posting four receptions for 50 yards and his first career touchdown in Sunday's 37-31 overtime loss to the Ravens.
"I mean, first of all, my heart hurts for Hunter," Allen said postgame. "I love that guy, and I'm praying for him and hope he has a fast recovery. And just with the opportunity that came tonight, I'm thankful to have it and to put my best foot forward and to help this team in any way I possibly can. And it was good. I had a good time."
Team leaders came away impressed with what they saw from the Clemson product on a rain-soaked afternoon, whether it was his duties in both phases of the offense – or having the courage to go airborne.
In the fourth quarter, Allen attempted to hurdle a defender on his way to a 21-yard catch on the drive that set up quarterback Matthew Stafford's 7-yard touchdown pass to wide receiver Demarcus Robinson.
"I thought he did a great job," Stafford said. "Obviously as a young guy in there, played a bunch of snaps. Happy for him on the touchdown. Great job on the long third down – just sending it down the middle there was a ballsy play, but it worked for him. I thought he did a really nice job. You know, those are some tough matchups both in the run game in the pass game. They got first-round picks all over the place. So I thought he did a nice job."
Head coach Sean McVay said they asked a lot of different things of Allen on Sunday and that the game isn't too big for him.
"Man, he played great, played great obviously," wide receiver Cooper Kupp said. "Hurts when Hunter goes down, but for him to step up and do what he did today was pretty special. I'd advise him to keep his feet on the ground when he's able to, but man, that was a huge play for us. And he did some really good stuff."
Allen said his mindset was just to do whatever he could to help the team win, whether that be in the run game, pass game or specials teams. Simple as it may be, it left a lasting impression.
"He's one of those guys, he's played in a lot of big time games, he's just nice and steady, but he's just a really good football player," McVay said. "He was really productive for us, and I'm excited about his future."