The Merseyside outfit are facing serious questions about their defence following a mixed run of results in the Premier League.
The Reds have already conceded 12 times in seven games to leave Jurgen Klopp’s men in seventh place ahead of the visit of Manchester United this weekend.
Klopp’s men squandered a lead to draw 1-1 with Newcastle United in their last fixture before the international break as Dejan Lovren and Joel Matip were caught napping for the Magpies’s equaliser.
Liverpool will welcome Premier League title contenders Manchester United to Anfield in their next Premier League game on Saturday afternoon.
Former Liverpool captain Souness urged the Reds’ back four to focus on their primary role in Klopp’s team: defending.
“It’s a common theme,” Souness told Sky Sports.
“Players who are in a good passing team start to admire their good play and forget to their jobs in the back four.”
Liverpool were linked with a move to sign Southampton captain Virgil van Dijk in the summer transfer window but failed to get a deal over the line.
The Reds signed four players but Scotland international Andy Robertson was the only defensive recruit in an £8m deal from Hull City.
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