Former Borussia Dortmund duo have had a torrid time in Manchester

In 2016, both Manchester clubs appointed new managers, with Jose Mourinho taking charge at Old Trafford and Pep Guardiola at The Etihad Stadium.

The "Mourinho era" at Manchester United began with the signing of a world-class attacking midfielder, Henrikh Mkhitaryan from Borussia Dortmund for a reported fee of £30m.

The 27-year old Armenian midfielder had impressed with his scintillating performances at Dortmund scoring 19 goals, creating 80 chances and 24 in 48 appearances in the 2015-2016 season.

His future looked promising and came into the United side with expectations very high among fans that his signing would fill a huge gap in the team's attack.

Mkhitaryan has made just one appearance in the last 13 fixtures for United this season

However, the Armenian had a stop-start debut season and wasn't able to positively affect the team as United scored just 49 goals in the Premier League, lowest among the top of 10 teams.

There was a clear lack of attacking game plan in the United side with the declining form of their star striker, Wayne Rooney and the failure of other forwards to deliver.

Mkhitaryan also has not delivered to the standard that has been expected of him. He started the season like a house on fire with 5 assists and a goal in the first couple of Premier League games this season and looked very sharp as a full pre-season and a long summer break helped him.

However, as the season has progressed, his performances have dropped down with the Armenian assisting just 1 goal in about 12 appearances. This has forced Mourinho to replace him with Jessie Lingard who is in the form of his life as Mkhitaryan has made just one appearance in the last 13 fixtures for United.

Mourinho likes to change his tactics depending on the game. This season, he has played with different formations and Mkhitaryan was a part of his team at the start of the season as a central attacking midfielder in a 4-2-3-1 formation.

With Mesut Ozil being linked to a possible move to United, Mkhitaryan would have to use the occasional chances he is getting to prove that he deserves the chance to continue as a Manchester United player.

On the other side of Manchester, the fans welcomed Pep Guardiola. He was the manager of the Dream Team i.e. the treble winning 2008-09 Barcelona side. Like Mourinho, he also chose to make a signing from the Dortmund midfield with the signing of ?lkay Gündo?an.

The City midfield was in decline due to the decline in performances of Yaya Toure and Fernandinho, so Gündo?an was signed to pair up with Kevin de Bruyne who had already made his mark with a spectacular first season at City.

Injuries have restricted Gündo?an to a mere 15 appearances for City in the 2016-17 season

Though Gündo?an was a first-team player, his appearances were limited at Dortmund due to injuries.

This pattern of injuries has continued since he moved to England as he has made fewer-than-expected appearances due to a succession of injuries.

However, in the few games, he has played, he has not disappointed scoring 2 goals, making 5 assists and creating 30 chances so far this season. In all, Gündo?an had a pass accuracy of 89% with 1727 completed passes

Guardiola feels that midfielders are the key to winning. He believes in keeping possession, creating chances and outshining the other team in every aspect.

With other City midfielders, de Bruyne, Fernandinho and David Silva performing splendidly, these three are generally first choices for Guardiola in a 4-3-3 formation and in order for him to be able to get a starting berth, Gundogan would have to step up to the level the aforementioned trio are currently at.

The big question is - should they never have left Dortmund? or it is the pressure of playing at such big clubs affecting their performances?