Manchester United fear new signing Leny Yoro could be set for a spell on the sidelines with the ankle injury he suffered during their friendly against Arsenal, a source has told ESPN.

Yoro was forced off in the first-half of the 2-1 defeat to Arsenal at SoFi Stadium in Los Angeles on Saturday in just his second start following his move from Lille.

The 18-year-old has not been able to train since and on Tuesday was pictured on crutches and wearing a protective boot on his left foot.

A source has told ESPN that club medical staff are still assessing the injury.

United have declined to comment with manager Erik ten Hag set to address the situation at a news conference on Thursday.

Yoro will miss the friendly with Real Betis in San Diego on Wednesday.

Losing Yoro, who signed for 52 million ($67m), represents a major blow to Ten Hag, who had hoped the Frenchman would replace Raphaël Varane in defence.

Varane has joined Italian side Como after leaving Old Trafford on a free transfer at the end of last season.

Sources have told ESPN that United are still in the market for another centre-back and retain an interest in Bayern Munich's Matthijs de Ligt and Everton's Jarrad Branthwaite.

Bayern want 42m for De Ligt while Everton have quoted more than 70m for Branthwaite.

United have already made two formal offers for Branthwaite, both of which have been rejected by Everton.

United also have concerns over the fitness of striker Rasmus Højlund, who was substituted in the first half against Arsenal after suffering a suspected hamstring injury.