Manchester United's players are reportedly growing restless with manager Jose Mourinho's black mood on the club's United States tour.

The Red Devils' pre-season campaign has not gone to plan for Mourinho, who has publicly complained about missing out on transfer targets and admitted to being concerned about the shape of his squad.

Results on the field have been far from ideal, too, with United drawing three of their friendlies and losing 4-1 to arch-rivals Liverpool last weekend.

Having called out Anthony Martial for failing to report back to the States following the birth of his baby boy, United's players are said to have reached breaking point.

According to the Daily Mail, a number of the playing squad and staff have become unsettled, as they are being made to tread carefully through fear of further upsetting the Portuguese.

A source is quoted by the publication as saying: "Jose's mood is dragging the whole tour down. He's clearly not happy with Ed Woodward and everyone else is suffering because of it."

Mourinho has spent £362m on players since arriving at Old Trafford two years ago - only Manchester City have splashed out more - but the former Real Madrid and Chelsea boss is still after two more recruits before the 2018-19 season begins next week.