Alexis Sanchez pictured in Manchester United kit ahead of Henrikh Mkhitaryan swap deal

Alexis Sanchez was pictured in a Manchester United shirt ahead of his move from Arsenal which is expected to go through on Monday.

A leaked shot of Sanchez - apparently taking a selfie while in a full United kit - was shared widely on Twitter on Sunday night.

The photo is believed to have come from his unveiling photoshoot at Old Trafford after he underwent his medical at United's training ground.

Earlier on Sunday, the Chilean posted a video on Instagram of him boarding a private jet, and retweeted an article defending him against accusations of 'mercenary' behaviour.

The 29-year-old forward will end his three-and-a-half-year association with Arsenal, with Mkhitaryan heading in the opposite direction.

Sanchez is set to become United’s best-paid player, with some reports putting his salary at £400,000 per week, and Steve McClaren has warned that salary could create dressing-room disharmony at United.

“That is the danger in the modern game and the problem I find in clubs,” said McClaren, the former England manager and Sir Alex Ferguson’s assistant when United won then treble in 1999.

“Wage parity is very important to players. Yes, they find out – at all levels – and if someone is paid a lot higher than others that can cause a problem.

“In the short term I don’t see a problem, but in the long term for Manchester United they will have to solve that problem.

“If he (Sanchez) is on the wages that is being bandied about then other players will know that when their contracts come up or they are in demand from other clubs.

“The others will be looking at renegotiation next season or the season after and getting to that (wage) level if they think they are at that level.”