Liverpool manager Jurgen Klopp called Philippe Coutinho's goal a "genius moment" after the Brazilian scored to finish off Manchester United in the Europa League on Thursday.
Liverpool had been leading 2-1 on aggregate at Old Trafford when Coutinho's away goal -- just before half-time of the second leg -- left United needing to score three more goals.
Neither team added to their tallies after that, meaning Liverpool progressed to the quarterfinals and keep alive their hopes of Champions League qualification through the continental route.
"Phil had a genius moment," Klopp said. "It was a brilliant moment and it decided the game tonight. He had a lot of good moments and he had a big chance before the goal. It was brilliant what he did. It was unexpected. It was a perfect goal."
Before Coutinho's goal, United had been threatening a comeback. They were 1-0 ahead on the night courtesy of Anthony Martial's penalty -- having already lost the first leg 2-0 at Anfield -- and were much-improved from the first leg.
Liverpool, though, looked dangerous on the counter-attack and soon made that threat a reality.
Klopp said: "We knew United would show a reaction. It was much more intense than the first game. We had a few problems in the first half with second balls. When we got the ball though, and used the time, we had brilliant moments and created wonderful chances."
Looking ahead to the next round, the Liverpool manager denied that he is hoping for a clash against his former club Borussia Dortmund, who eased past Tottenham Hotspur in their match.
Klopp said: "Why would I want the strongest team in the next round? I am not so silly. All my friends in Dortmund want to play us -- but only in the final in Basel."
The other teams in the draw for the quarterfinals are Villarreal, Sparta Prague, Athletic Bilbao, Shakhtar Donetsk, Sevilla and Braga.
Klopp said: "We deserved to go to the next round and that feels really good."
Liverpool left-back Alberto Moreno missed the game at Old Trafford as a precaution, having suffered a hamstring problem in training the previous day, and the club will assess him on Friday.
James Milner played as a makeshift left-back against United, while his opposite player Juan Mata gave a disappointing display on the whole.