Manchester United are in danger in being dumped out of their second continental competition of the season after Liverpool inflicted a deserved 2-0 defeat upon their north west rivals at Anfield on Thursday.
Goals from Daniel Sturridge and Roberto Firmino in either half secured the result for Jurgen Klopp's team, to leave United with a mountain to climb in next week's last-16 return leg at Old Trafford.
It would have been a far greater margin were it not for David de Gea, who made at least five saves of the highest quality.
But could any of the Spaniard's teammates match his performance? Here are their ratings out of 10:
David de Gea 8/10 - Produced eye-catching stops from Philippe Coutinho (twice), Daniel Sturridge, Adam Lallana, and Nathaniel Clyne. It would have been a rout without him.
Guillermo Varela 6/10 - Steady and assured despite the presence of those around him who weren't. Gradually establishing himself as United's first-choice right-back.
Chris Smalling 5/10 - Wasn't his usual self. One missed header almost allowed Sturridge to score in the first half.
Daley Blind 5/10 - Was moved to left wing-back at half-time, having found Liverpool's movement difficult to keep track of.
Marcos Rojo 5/10 - Yet to really impress for United and continued in the same vein here. Looked off the pace, whether at left- or centre-back.
Marouane Fellaini 5/10 - Never been a playmaker. That said, he improved briefly after the break but should have seen red for an elbow on Firmino.
Morgan Schneiderlin 5/10 - Another who was suddenly more involved in the second half. Was decent in possession but had Jordan Henderson with his second-half half-chance, it would have been the result of the Frenchman's poor tracking.
Marcus Rashford 5/10 - Misjudged an early half-chance and spent the rest of the half helping out Varela at right-back. Subbed at the break, but shouldn't be too downhearted.
Juan Mata 5/10 - Saw more of the ball after the change of system but, despite his tricky feet he struggled to pull anything out of the bag.
Memphis Depay 4/10 - Gave away the penalty, although there was some debate over the decision. Regardless of that, this was another of his off-nights.
Anthony Martial 5/10 - Isolated throughout. On the rare occasion he did see the ball, Liverpool's defence swarmed around the Frenchman, snuffing him out.
Michael Carrick (for Rashford 45) 5/10 - Failed to deal with Henderson's cross, presenting Lallana with the simple task of squaring for Firmino to score. That said, United briefly improved following his introduction, which should have arguably been in midfield and not at the back.
Bastian Schweinsteiger (for Schneiderlin 79) 5/10 - Little time to make an impact.
Ander Herrera (for Mata 79) 5/10 - See Schweinsteiger. His introduction was too little too late.