Liverpool's Van Dijk undergoes successful knee surgery

Liverpool centre back Virgil van Dijk has undergone knee surgery after he damaged knee ligaments in the Merseyside derby against Everton earlier this month, the Premier League club said on Friday.

Van Dijk was injured early in the 2-2 draw when he was at the receiving end of a reckless challenge by Everton goalkeeper Jordan Pickford, which left Liverpool manager Juergen Klopp fuming.

"The Liverpool defender's planned operation took place in London and was conducted successfully," the club said in a statement.

"Van Dijk will now immediately focus on the beginning of his rehabilitation with the support of the Reds' medical department."

The club did not give a time-frame on his return, with the Dutch defender potentially ruled out for the rest of the season due to the nature of the injury.

Liverpool, second in the league standings behind Everton on goal difference, play West Ham United on Saturday.