Henrikh Mkhitaryan
Mkhitaryan has not been seen in a United shirt since 10 September. Getty

Henrikh Mkhitaryan was once again notable only by his absence as Manchester United saw off Manchester City in their fourth round EFL Cup tie on Wednesday.

The 27-year-old, widely regarded as the best player in the Bundesliga last season, has managed just 114 minutes of first-team football this term and hasn't even made the bench since he suffered the ignominy of being hauled off at half-time in the Premier League meeting between the Manchester clubs in September.

So what is exactly going on with the £27m signing, then? IBTimes UK looks back on his bleak start to life at Old Trafford.

6 July – Manchester United complete the signing of Mkhitaryan from Borussia Dortmund. He described his arrival at Old Trafford as a "dream come true".

19 August – After being left on the bench in the club's opening two games of the season – the Community Shield meeting with Leicester City and Premier League opener with Bournemouth – Mourinho insisted the omission was merely down to having more appropriate options in mind for those games.

"I went to the game against Leicester and I was reading the game and I thought we needed the speed of Jesse Lingard," the United boss said.

"And against Bournemouth, I thought they wanted to press really high, and a player like Mata coming inside could reach some spaces behind the lines of pressure and it could be very useful for us."

27 August – After playing 14 minutes off the bench against Southampton, Mkhitaryan was given 30 with his side desperately chasing a goal away to Hull City with the score tied at 0-0. While Wayne Rooney and Marcus Rashford combined to score the late winner, Mkhitaryan was the catalyst, changing the game with his driving runs from midfield and telling passing.

Henrikh Mkhitaryan
Mkhitaryan provided a thrilling cameo against Hull. Getty

1 September – While representing Armenia against Czech Republic, the attacking midfielder was forced off after just 38 minutes following an off-the ball collision with Marek Suchy.

3 September – The Armenian FA confirmed Mkhitaryan had suffered 'an injury in the lower third of the left thigh muscle' that would rule him out of their next qualifier with Denmark, with the first Manchester derby of the season just a week away.

10 September – Having told reporters Mkhitaryan was "ready to help us", Mourinho selected the attacking midfielder to start against Pep Guardiola's City side at Old Trafford. Both he and Jesse Lingard lasted just 45 minutes after thoroughly wretched performances.

In his post-match interview, Mourinho suggested the Armenian struggled with the weight of the fixture. "Some of the boys, they felt the dimension of the game. Everything around the game: the derby, the big game, the focus, the attention. Some of the guys, they felt it."

12 September – Ahead of a Europa League clash with Feyenoord, Mourinho suggested players who disappointed against City would be dropped.

14 September – Ahead of the Feyenoord game, The Times reported Mkhitaryan had in fact aggravated a thigh injury against Manchester City that would rule him out of the trip to Watford four days later and the EFL Cup clash with Northampton Town the following week.

25 September – United swept aside Premier League champions Leicester in their most convincing performance of the season, but again, there was no Mkhitaryan. Mourinho stressed after the game the Armenian was no longer injured, but was not 100 % ready, both physically and mentally. He said: "When they are not 100%, I always think that in these difficult moments - when you really feel you have to win the match - I prefer always to go with players who are 100% ready, from their physical and mental point of view."

Henrikh Mkhitaryan
The Armenia international suffered from a thigh injury in September. Getty

1 October – Ahead of the league clash with Stoke City, Mourinho was again asked about his player and again suggested he was fit. "Micki is training now with the team," he told reporters. He left it at that and again there was no sign of the Armenian as United drew at home to the Potters.

3 October – As members of the United squad departed for the second international break of the season, the club made a plea to the Armenian FA for Mkhitaryan to remain in Manchester because he was still 'undergoing late stage rehabilitation from the left thigh muscle injury." The statement added the injury meant he was unable to "train fully without restrictions or play competitively". United's request was granted he missed Armenia's two World Cup qualifiers.

19 October – United's huge clash with Liverpool came and went and still no Mkhitaryan – despite Mourinho assuring he was available for selection. Ahead of their next match, a Europa League clash with Fenerbahce, Mourinho said the player was "training without any limitations" but refused to confirm if he would start.

Henrikh Mkhitaryan
Mkhitaryan has started just once with his previous four appearances coming off the bench. Getty

20 October – So why was Mkhitaryan left out of the Fenerbache game? Mourinho explained his decision and again, suggestions the player was not training at the level he expected were evident.

"The situation is that we played with Lingard, with Mata and Martial," Mourinho told reporters. "I am not an Einstein, I don't know a tactical system to play with four wingers at the same time. He has to work more to get the intensity and the real fitness to play at the high level.

He added: But he is ready. He is ready very soon."

23 October – 'Soon' didn't mean the trip to Stamford Bridge. Again he was left out as United were hammered 4-0.

26 October – Ahead of the EFL Cup clash with City, the Manchester Evening News reported Mkhitaryan was part of the 20-man party who arrived at the Lowry Hotel Wednesday afternoon. Just before 7pm the official squad was announced and again, no Mkhitaryan. Shortly after, United's Twitter account posted a video of the squad trotting off the team bus and into the dressing room. The former Borussia Dortmund star was among that party, but that's all we saw of him that evening.

28 October - The next time Mourinho will address the press and inevitably, will be asked about United's mystery man. With Burnley coming to Old Trafford, the United boss may feel that game will be an appropriate test to see where his player his physically and mentally. Then again, maybe not.