Liverpool have been a dealt a huge blow with news that centre back Virgil van Dijk needs surgery on damaged knee ligaments sustained in Saturday's Merseyside derby draw against Everton.
The Premier League champions confirmed on Sunday that the Dutchman, ever-present in the league for the last two seasons, would need an operation, although they did not say how long he would likely be missing.
Van Dijk was substituted early in the game when Everton goalkeeper Jordan Pickford made a reckless challenge in the box, which left Liverpool manager Juergen Klopp fuming.
"Liverpool can confirm Virgil van Dijk will undergo surgery on the knee injury he sustained during Saturday's 2-2 draw at Everton," the club said in a statement.
"The centre back damaged knee ligaments following an incident involving Blues goalkeeper Jordan Pickford after six minutes at Goodison Park."
Van Dijk has reportedly damaged cruciate ligaments, an injury that normally requires months of recovery, potentially ruling him out for the rest of the season while also dealing a blow to the Netherlands ahead of the Euros next year.
"If you asked me at the start of the season who is the one player Liverpool don't want to be missing for a chunk of the season, for me it would be Van Dijk," former Liverpool midfielder Graeme Souness told Sky Sports.
"He is the catalyst for everything they do. It's a major blow and the last thing they needed."
Reigning league champions Liverpool are third in the standings after five games, three points behind Everton.
Van Dijk was bought for 75 million pounds -- a club-record signing -- and has played 50 games in each of the last two seasons for Liverpool.
Liverpool are also short in central defence with Joe Gomez and Joel Matip the only fit senior centre backs available ahead of a congested schedule where they play six times in 18 days before next month's international break.
Liverpool begin their Champions League group stage campaign at Ajax Amsterdam on Wednesday and Van Dijk's absence leaves another hole at the back with goalkeeper Alisson Becker also sidelined with injury.