Manchester United midfielder Henrikh Mkhitaryan has revealed he “many hard nights” alone in his apartment during his second season at Borussia Dortmund under Jurgen Klopp.

The Armenian arrived at Dortmund for £23.6million in 2013 as the replacement to Mario Gotze – who moved to Bundesliga rivals Bayern Munich.

Mkhitaryan could only manage three goals in his second term at the Westfalenstadion as Dortmund were stuck in a relegation fight for much of the season, in comparison to the nine goals and ten assists from the previous campaign.

And the midfielder, who now plays under Jose Mourinho at United, has revealed Dortmund’s struggles hit him hard.

“It was a very hard period for me. The first season was O.K, but the second season was a disaster, not only for me, but also for the club,” said Mkhitaryan, writing for The Players’ Tribune.

“We were losing so much, and I felt like I was having no luck. Not only was I not scoring, but I was not assisting, which is very unlike me. I had been signed for a lot of money, and I put a lot of pressure on myself.

“I had many hard nights in my apartment in Dortmund, all alone, just thinking and thinking. I didn’t want to go outside, even to have dinner.”

The 27-year-old was reinvigorated under Thomas Tuchel in his third and final season at the German side and he has put it down to his former boss making him “happy again”.

“Thomas Tuchel, came to Dortmund before my third season, and he changed everything for me,” added Mkhitaryan. “He came to me and said, ‘Listen, I want to get everything out of you. He looked at me very seriously, and said, ‘Micki, you are going to be great.’

“That meant everything to me. After the season I had, I didn’t think I could be a star. But he did it.

“He got everything out of me that season, and it was because I was happy again.”