The Reds extended their winless Premier League run to three games on Sunday afternoon after Wayne Rooney’s 78th-minute strike secured a 1-0 victory for Manchester United at Anfield.
Klopp has already lost five of his 14 Premier League games since taking over the reins from his predecessor Brendan Rodgers following October’s Merseyside derby.
The former Borussia Dortmund manager has already signed Serbian youngster Marko Grujic and one-time England defender Steven Caulker on a loan deal for the remainder of the season.
But ex-Liverpool left-back Riise believes the Reds need a stronger core to their side following a disappointing run of results in the Premier League.
I feel we need a stronger central line through the team.
— John Arne Riise (@JARiiseOfficial) January 17, 2016
Liverpool are in ninth place and eight points behind fourth-placed Tottenham Hotspur in the hunt for a top-four finish and Champions League football.
The Reds host Exeter City in their FA Cup third-round replay on Wednesday night before a trip to Norwich City in the Premier League next weekend.
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