Liverpool manager Juergen Klopp hopes the ankle injury which defender Joel Matip suffered during Sunday's friendly win over Wigan Athletic is not a serious one.

The German-born Cameroon international, who joined on a free transfer from German Bundesliga side Schalke 04 at the end of last season, limped off in the final stages in Sunday's 2-0 win over the Championship side.

"I hope it's only a minor problem. It's not too serious, hopefully. We had to make the decision of Joel or Dejan (Lovren), who has to play the whole 90 minutes?" Klopp told the club's website.

With defender Mamadou Sakho, who underwent treatment for a long-standing Achilles problem, set to miss the Premier League opener against Arsenal on Aug. 14, Klopp is confident the 24-year-old will resume training on Tuesday.

"It's the foot he had problems with in the past and then he had a little bit of pain when pre-season started because of the intensity. He said he's had it one or two times already. He's used to it," the former Borussia Dortmund boss added.

"I think tomorrow (Monday) he'll rest, then he can go again."

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