Elliott, though, was up for the task. He picked up two assists in the second half - assists that ultimately won the game. 1-1 when he came on, 3-1 when he'd finished.
The first saw Elliott collect the ball inside the right of the box. He shifted it onto his left and threaded the needle for Luis Diaz to head home from close range. The second was a clip into the box from Elliott that found Darwin Nunez for a fine header - a brilliant finish from the Uruguayan.
Two big moments, then, both created by Elliott. It was a massive performance off the bench, and not for the first time this season. This one was particularly notable, though as the 20-year-old was the decisive player in the game.
His two assists move him onto three in the Premier League this season, one more than last term, and also means that Elliott has as many assists as starts.
That's the big point coming out of this. Elliott should be starting more games and he talked earlier in the season about wanting to.
"For me, I don't really want to be known as a super sub," he said. "It's a great headline as well, it's a nice one, but at the same time, I want to be in the team.
"It's time for me to establish myself in that position again and hopefully get a good run of games. At the same time, I need to be patient as well and maybe be the super sub at the moment."
Well, it's time for Liverpool to grant Elliott his wish. As big games start to come thick and fast, Klopp should lean into him more - Elliott has more than earned his chance.