Liverpool defender Virgil van Dijk faces a battle to be fit for their Champions League round 16 clash with Real Madrid.

Boss Jurgen Klopp revealed his defensive kingpin will be out for "more than a month" with a hamstring injury and is battling to make the last-16 first-leg tie at Anfield on February 21.

Klopp said: "It's absolutely a big blow — the diagnosis is really harsh.

"It's very hard on Virgil but he has played an incredible number of games in the last years.

"He's never had a muscle problem before — it was just one sprint too many for him."

Van Dijk was crocked as Liverpool went down 3-1 to Brentford on Monday.

Klopp added: "Virgil was a surprise to us. He didn't feel a lot.

"It's not short term and it's not long term but he will be out for a few weeks definitely."