Liverpool have suffered a significant injury blow after it was confirmed Adam Lallana has been ruled out injured until at least October.
Coach Jugen Klopp said Lallana would miss "a couple of months, not weeks," and a source close to the club confirmed the midfielder would be sidelined for a maximum of three months.
Lallana suffered a thigh injury during Liverpool's Audi Cup defeat to Atletico Madrid in Munich on Wednesday and will now miss the opening few months to the 2017-18 campaign.
The 29-year-old has become an integral part of Klopp's side after being moved into a central-midfield role at the start of last season.
"This is certainly not news we would have wanted," Klopp told Liverpool's website. "Unfortunately, the damage is such that it will likely mean Adam is out for a couple of months not weeks, so I think we can pretty much rule him out of August and September.
"Beyond that we will monitor and wait and see. He is a boy with a world-class attitude to everything professionally and he has always come back in good time from injury setbacks since I have been here, so we will see."
In Lallana's absence, Klopp could turn to Emre Can or Marko Grujic to fill his spot in midfield.
Liverpool begin their Premier League season Aug. 12 at Watford before facing Hoffenheim in the Champions League playoff round starting Aug. 15. Lallana will miss games against both Arsenal and Manchester City in the early stages of the Premier League season.
He will also be in a race to be fit for England's final two World Cup qualifiers, against Slovenia on Oct. 5 and away to Lithuania three days later.