Henrikh Mkhitaryan's start to his Manchester United career has seen him remain firmly on the sidelines of Jose Mourinho's struggling squad.

And just 24 hours after United huffed and puffed in their 0-0 stalemate with Burnley at Old Trafford, the out of favour Mkhitaryan was pictured leaving his team's Aon Training Complex having worked out alone.

The Armenian international, 27, moved to the Premier League from Borussia Dortmund this summer, signing a four-year contract for a fee of £23.6million. But he's made just one start under Mourinho since - the Manchester derby defeat by City.

Henrikh Mkhitaryan was pictured leaving Manchester United's Aon Complex on Sunday

Mkhitaryan is on the fringes of the United squad and sat out the scoreless draw with Burnley

The Armenian (back left) is pictured in the stands during United's 0-0 stalemate on Saturday

Mkhitaryan left United's training ground in his white Lamborghini.

On Sunday, Mkhitaryan took to Instagram to write: 'Better days will come for us! We march on. One for all and all for one! #mufc.'

Mkhitaryan was once again left out of the United squad against Burnley, watching from the stands as the men in red failed to break down the Clarets and saw manager Mourinho and Spanish midfielder Ander Herrera sent off.

MKHITARYAN FOR UNITED THIS SEASON Appearances: 5 Goals: 0 Assists: 0 Minutes played: 104 Advertisement

After a spectacular 2015-16 campaign with Dortmund, much was expected of Mkhitaryan when he arrived in English football.

But the talented winger suffered the humiliation of being substituted at half time after a wretched performance against City. He has not been seen on the pitch since.

The former Shakhtar Donetsk midfielder hasn't been helped by a lingering thigh injury, but was declared fit before United faced Fenerbahce in the Europa League.

Nonetheless, he has failed to appear in a red shirt since, raising significant questions over the future of a man who currently looks like an expensive mistake.

That said, Mourinho was at pains to point out before the draw with Burnley that he believes Mkhitaryan will eventually come good at United.

Mkhitaryan posted this picture to Instagram with the caption: 'Better days will come for us! We march on. One for all and all for one! #mufc'

Mkhitaryan hasn't been seen in a United shirt since a poor display in the Manchester derby

The 27-year-old was substituted at half time during his team's defeat by bitter rivals City

United manager Jose Mourinho said before the Burnley game Mkhitaryan was still in his plans

'We believe in him and of course we believe that sooner or later there will be no problem,' Mourinho said earlier this week.

'But Mkhi needs time to become the top player he can be. With some players, their profile is adapted to come and play.

'Some others need more time to feel the intensity and the aggression (in England), the game without the ball, the competitiveness. Many times players come from different countries and the style of football is different.

'There's no other country where it doesn't matter the team you play against, you have to play at the highest level. If you don't, you have no chance.'

Despite barely featuring so far this term, United have rejected any notion Mkhitaryan could be quickly moved on in January. The 27-year-old, who speaks six languages, is said to be 'an absolute gentleman' and popular with Old Trafford staff.

But Sunday's solitary training session is hardly something which will reassure the player, Mourinho moving to compare Mkhitaryan to Angel Di Maria this week. He will hope his United career doesn't go the same way as that of the Argentinian misfit.

Mkhitaryan is pictured after signing for United following his move from Borussia Dortmund

Mkhitaryan is popular at United but Mourinho clearly feels he is not yet ready to play

'Mkhi is not injured. He is training with the team 100 per cent, there is no limitation in terms of his fitness-related injuries,' Mourinho added.

'Willian - he arrived at Chelsea, had problems to play. He went through a process then after he became a top player. Then the next season he became absolutely phenomenal and still is.

'When Di Maria arrived at Real Madrid, he also had to learn a lot about his game and a new reality. Sometimes it happens. Attacking players sometimes arrive and go straight to success. Other times it takes a little more time.