Liverpool boss Jurgen Klopp lamented his side’s “massive mistakes” in the remarkable 7-2 thrashing at Aston Villa before suggesting Alisson Becker could be sidelined for the next six weeks.

Ollie Watkins registered a first-half hat-trick and John McGinn, Ross Barkley and Jack Grealish, netting a brace, also scored against Klopp’s shell-shocked Premier League champions as they were dismantled at Villa Park.

Liverpool’s goals were both scored by Mohamed Salah, at 2-0 and 5-1 down.

The rout, which saw Villa lead 4-1 at half-time, started with Watkins’ fourth-minute opener as the hosts punished an error by Reds goalkeeper Adrian, who had come into the side after first-choice stopper Alisson sustained a shoulder injury in training.

It was the first match in which a Klopp team had conceded seven goals in his managerial career, and the first occasion for Liverpool since a 7-2 loss to Tottenham in 1963.

Klopp said in his post-match press conference: “The strange result is because Aston Villa played really well and we did in different areas particularly bad.

“Pretty much everybody made massive mistakes around the goals, and the first one was obviously Adrian. That was a big mistake but how we reacted was an even bigger mistake.”

He added: “In different challenges Aston Villa definitely wanted it more than us. That’s something I saw and don’t like.

“A game like tonight should not happen, 100 per cent.”

Last Monday Klopp took issue with Sky Sports pundit Roy Keane claiming Liverpool had been sloppy at times during their 3-1 win against Arsenal.

In his interview with Sky Sports after the Villa match, Klopp, having described his team as having “lost kind of the plot” after the opening goal, said: “Last week Mr Keane said we defended sloppy, it wasn’t sloppy tonight it was just bad.”

When Klopp was asked in his press conference about Alisson, he said the Brazilian had “no chance” of playing in the next match at Everton on October 17 and that “four weeks could be possible, six weeks is maybe more likely”.

As Villa brought Liverpool’s 100 per cent start to the Premier League season to a shuddering halt, they extended their own – they have opened a league campaign with three successive wins for the first time since 1962-63.

Villa boss Dean Smith, whose side are now second in the table, said when asked where the result ranked in his career: “It has to be right at the top.

“To go and get a performance like that against an exceptional team takes something special. It was a special performance.

“I am extremely proud. They executed a gameplan to perfection but it was not just that, it was workrate and ethic. We played exceptionally well and I am proud of everyone.”