Jurgen Klopp made three changes to his side from the 2-0 win over Wolves in midweek, with Andy Robertson, Jordan Henderson and Cody Gakpo coming in.
Henderson was expected to start in a big-game tie, but the assumption was that Elliott would drop out and Bajcetic be retained amid an excellent run of form.
But when the teamsheet was released at 3.30pm, the news emerged that Klopp had backed his No. 19 over his slightly younger team-mate.
Its just a mix of what we need. The experience and the football part, he told Sky Sports on his midfield setup.
Harvey played a really good game against Wolves. We set a new record for this season, at least in counter-pressing situations. Harvey was very much involved in that.
And on top of that hes a good connector, these kinds of things.
Hendo, with his experience, thats why [he starts]. It says nothing about Stefan. He was outstanding.
There were other options as well. So thats good.
That didnt happen that often this season, but we have them now and thats why we decide for that.
The hope will be, then, that Elliott brings intensity in a midfield alongside Henderson and Fabinho, again starting as the left-sided No. 8 in Klopps 4-3-3.
His combination play with Robertson and Darwin Nunez will be vital, but as the manager pointed out, so will his ability to win the ball back quickly.
Bajcetic remains an option, of course, on a bench that includes the likes of Diogo Jota, Fabio Carvalho and Roberto Firmino.
Jota was always expected to drop out after two consecutive starts, with Gakpo taking his place.
Klopp explained that while the Portuguese that really good against Wolves, he did not want to force it after a four-month injury.