Gordon had two sighters early in the second half as the home side set about that task – and by the hour mark, the attacker had hauled them level.
First, he was in the right place to tuck home from yards out after a slick Reds move along the right-hand side had caused a bit of pinball.
His second was a beauty. Collecting a pass from Lewis Koumas just around the ‘D’, Gordon arced a lovely strike off his left foot into the top right corner.
And a sensational spell of three Liverpool goals within the space of four minutes was completed when, with a helping hand from Gordon, the top corner was again found by Nyoni.
Palace responded strongly and had opportunities as time ticked away, with Mrozek thwarting Justin Devenny, Mathurin and Dan Imray along the way.
But Lewtas’ charges held firm to preserve their 3-2 lead and clinch the spot in the last eight when the play-offs continue next weekend.
TEAM
Liverpool U21s: Mrozek, Frauendorf (Spearing, 79), Davidson, Nallo, Pinnington, McConnell (Blair, 85), Gordon, Pilling, Koumas, Nyoni, Morrison.
Unused subs: O. Kelly, K. Kelly, Laffey.
NEXT UP
Liverpool will face either Tottenham or Aston Villa – who meet on Monday afternoon – in the quarter-finals.
The Reds will be away from home for that tie, which is set to take place on a date between May 10 and 13.