But Joe Willock earned a point for the Magpies as the on-loan Arsenal man equalised in the fifth minute of added time - with the 1-1 draw leaving Jurgen Klopp's side four points off fourth spot with five games left to play.
“We don't learn our lessons, we keep making the same mistakes," said Robertson after Saturday's Anfield clash. "Teams always have a chance against us, they always build in confidence."
Robertson's manager Klopp admitted his side paid for failing to take their chances - and questioned whether they deserved to qualify for next season's Champions League.
He told BT Sport: "I don't think you can create many better chances than we did. We scored a wonderful goal but didn't finish the game off."