Jurgen Klopp has been left to count the cost of an of international break during which his Liverpool squad suffered another seismic injury ahead of the visit of the Premier League's co-leaders Manchester United. Sadio Mane has returned from Senegal duty with a hamstring injury which will keep him out for six weeks, a stretch which could see him miss up to nine games.

The forward joins an injury list which already includes Adam Lallana, Nathaniel Clyne, Danny Ings and Adam Bogdan – none of whom have played this season. It leaves Klopp, who already has a number of key decisions to make with the Reds having only won three of their seven league outings this term, with a number of selection dilemmas heading into the weekend.

It starts in goal where Simon Mignolet and Loris Karius have been rotated through the campaign though the Belgian has started all but one of the games in the Premier League. He can be expected to be retained for the visit of United.

Among the chief concerns for Klopp this season has been the proficiency of his defence, which has shipped 20 goals in 11 matches. Joe Gomez has played the full 90 minutes in the last two league games and is expected to be called upon, with the ever-present Joel Matip an all-but certain starter in the centre.

Dejan Lovren would be the natural choice alongside the Cameroon international but concerns over a long-term back problem makes him a doubt. The Croatian has admitted to take five painkillers to get through matches and missed the recent defeat to Manchester City and draw with Burnley. With the top flight's top scorer Romelu Lukaku likely to represent a physical test in attack, Liverpool can ill-afford to have a passenger in their problem position. Ragnar Klaven waits in the wings.

Completing the back-four is likely to be the more secure Andrew Robertson, who despite starting just three times this season represents the reliable selection ahead of Alberto Moreno. The Spaniard is prone to errors while his positional sense could be exposed by the rampaging Antonio Valencia and crafty Juan Mata. Former Liverpool forward John Aldridge feels the Scot represents the best option at both ends of the pitch.

Jurgen Klopp
Klopp faces a number of selection decisions ahead of the visit of United. Getty Images

The absence of players further forward means Liverpool are likely to try and outnumber United in midfield with a tight three. Captain Jordan Henderson and Dutchman Georginio Wijnaldum are staples of the team under Klopp but expected Emre Can to complete the trio. James Milner may be held back to help close the game down in the dying embers.

Can is subject of speculation over his future but there can be no doubts over his form having played 90 minutes for Germany in their final World Cup qualifier against Azerbaijan, and firing home a blistering 25-yard strike in a 5-1 win.

The loss of Mane means Philippe Coutinho will no doubt be moved forward into his favoured position on the left, with Mohamed Salah – fresh from guiding Egypt into their first World Cup since 1990 – occupying the right side as he has done since arriving from Roma.

Klopp is left with a straight choice between Roberto Firmino and Daniel Sturridge. Though the England forward has five goals in 15 appearances against United, it could be Firmino's superior link-up play with Salah and Coutinho and ability to operate in a fluid Liverpool system which gives him the edge.

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