Liverpool cruised into the fifth round of the FA Cup with a 5-2 rout of Championship side Norwich City on Sunday, to kick off Jurgen Klopp's long goodbye at Anfield.

Liverpool's beloved manager announced on Friday that he would leave the Merseyside team at the end of this season, his ninth at the helm.

The eight-time FA Cup winners had goals from Curtis Jones, Darwin Nunez, Dioga Jota, Virgil van Dijk and Ryan Gravenberch.

Liverpool will next play either Watford FC or Southampton after that fourth-round game earlier on Sunday ended in a 1-1 draw thanks to a last-gasp goal by Southampton's Stuart Armstrong to force a replay.

Ben Gibson and Borja Sainz scored for Norwich City, who are ninth in the Championship, 28 spots below Premier League leaders Liverpool in England's football pyramid.

Wolverhampton Wanderers' 2-0 victory in their fourth-round match at West Bromwich Albion on Sunday was interrupted for nearly 40 minutes due to clashes involving the two sides' supporters.

Wolves were leading 2-0 when projectiles were hurled onto one end of the pitch in the 82nd minute, sparking a brawl in a corner at The Hawthorns.

Matheus Cunha and Pedro Neto scored for Wolves, whose manager Gary O'Neil called the disturbances "really disappointing".

"Up until that point it was a good tie with good atmosphere," O'Neil told ITV. "How people behave at football is really important and we need to look at that, make sure everyone is safe. When we came back out the atmosphere had gone, it was really sad to see."

The delay prompted officials to push back the draw for the FA Cup fifth round “ originally scheduled for just before the Liverpool-Norwich kick-off “ to halftime of that game. (AFP)