Scotland skipper Andy Robertson is part of the best full-back pairing in the world, according to former England striker Peter Crouch.

Left-back Robertson and right-back Trent Alexander-Arnold were again crucial for Liverpool as the Reds surged eight points clear at the top of the English Premier League with Sunday’s 3-1 victory over title rivals Manchester City.

Robertson’s magnificent curling cross set up Mohamed Salah for Liverpool’s crucial second goal and the former Dundee United and Queen’s Park player also turned in an assured defensive display.

And Crouch, who spent three years with Liverpool from 2005, insists the 25-year-old and Alexander-Arnold on the opposite flank are better than anyone else in world football.

He said: “With what they do for this Liverpool team, Andy Robertson and Trent Alexander-Arnold are redefining the way full-backs play.

“With their runs forward and balls into the box they have always offered such an attacking threat, along with the front three, but now they are passing to each other too.

“I remember when I was playing for Liverpool, the full-backs were passing it inside to [Steven] Gerrard or Xabi Alonso, who would play the diagonal balls forward.

“Well, Trent is doing that himself now, from his position, and he is doing it just as well as Gerrard or Alonso.

“Then you have got 'Robbo' on his bike and pelting forward to get on the end of them, creating chances like he did for Salah’s goal against City.”

Crouch added to the BBC: “It is a joy to watch at times and they really are outstanding.

“I don’t know a better full-back pairing in the world at the moment, and they are another reason why this Liverpool team is going to be so hard to stop.”