A thumping strike from Harvey Elliott was enough to give FA Cup holders Liverpool a 1-0 win away to Wolverhampton Wanderers in a third-round replay.
Teenage midfielder Elliott burst forward with plenty of space to run into and unleashed a fizzing strike which flew past Wolves' goalkeeper Jose Sa in the 13th minute of Tuesday's clash at Molineux.
Wolves were passive for much of the first half before growing into the match after the interval but Liverpool kept them at bay to earn a first win in four games in all competitions.
"It feels like ages ago we had a feeling of winning and playing well," Klopp said.
"We had to fight hard at the end of the match, which we controlled for long periods. It is great and the reaction we wanted to see."
Prior to kick-off, Wolves announced the signing of Spain midfielder Pablo Sarabia from Paris St Germain in a deal worth five million euros ($7.7m).
Coach Julen Lopetegui has also added Brazilian forward Matheus Cunha and Gabon midfielder Mario Lemina to his squad during the January transfer window.
Cunha had Wolves' best opportunity when he won a free header in the area but could not get enough power on it to trouble Liverpool goalkeeper Caoimhin Kelleher.
The result set up a fourth-round tie away to Brighton, where Jurgen Klopp's side were thrashed 3-0 in the Premier League on Saturday in a performance described by the coach as the worst he could remember in his eight years in charge of the Merseyside club.
West Bromwich Albion joined Liverpool in the fourth round by routing Chesterfield 4-0 at home, with Socceroo Tom Rogic among the scorers.
They will next face Bristol City, who scored a decider through Sam Bell eight minutes from the end of extra time to win 2-1 at Swansea.
Birmingham City came from behind to beat Forest Green Rovers 2-1 and Luton Town won 2-1 at Wigan Athletic.
- with AP