Liverpool boss Jurgen Klopp believes Ole Gunnar Solskjaer should be made Manchester United's permanent manager and praised the Norwegian for being able to combine everything United stood for under Alex Ferguson with a modern tactical approach.

Liverpool, whose 3-1 win over United at Anfield in December led to Jose Mourinho's sacking and Solskjaer's appointment until the end of the season, head to Old Trafford for the reverse fixture on Sunday.

Solskjaer's impact on a team that was labouring under Mourinho has surpassed expectations, and he has guided United into fourth place in the Premier League on the back of a run of eight wins and a draw in nine league games since taking charge.

"It must be one of the best records ever, mustn't it?" Klopp told a pre-match news conference on Friday. "I'm really happy for him. It's not the best news for us but for all Manchester United fans its brilliant.

"They've brought in all the things Sir Alex Ferguson stood for with all the new things in football. That makes them a threat again. They are really back on track. Good for them.

"Now he's in charge and there's no doubt he will be the manager next year as well. That is clear. Can you imagine if they brought in a new manager? He deserves (the job) 100 percent."

Liverpool head to Old Trafford placed second in the league on goal difference behind Manchester City, who have played one game more.

Klopp said Solskjaer's success was built on the Norwegian being able to get the best out of players such as Paul Pogba, Ander Herrera and others, who struggled under Mourinho earlier in the season.

"They have found a solution and it has worked out," Klopp added. "We see that with Pogba and with Herrera in outstanding shape. They were all good before and now they are full of confidence and use their potential.

"It's not that we go there and we are a weak opponent... we are a pretty well organised football team with a lot of potential. If we can (live up to it), then it will be a tough one for United."

Liverpool centre backs Dejan Lovren and Joe Gomez will miss the game due to injury.