FC Rostov head coach Kurban Berdyev has revealed what was in a mysterious box presented to him by Manchester United’s Jose Mourinho, ahead of the club’s Europa League match.

Mourinho was snapped handing a stylish black box to Berdyev before the second-leg of the Europa League tie, which Manchester United won 1-0.

There was a wealth of speculation online as to what the box contained, with Rostov posting a picture of the gift to their Twitter page.

Mourinho watching the first-leg in Russia (Man Utd via Getty)

The image showed a small replica of the Europa League trophy with the Manchester United crest emblazoned on it and ‘FC Rostov, Round of 16, 2016/17’ written underneath.

Rostov posted the image along with a message reading: ‘Inside the black box from Jose Mourinho was this super-cool keepsake!’

Relations between the two clubs during their Europa League tie were extremely cordial, with Rostov handing out free blankets to the 200-strong group of United fans that travelled to Russia for the first-leg.

The red blankets, which had “Gentlefan Russian Warm Welcome” written on them in white lettering, did not go unnoticed by Mourinho, who praised Rostov’s hospitality.

United supporters wearing their blankets in Rostov (Man Utd via Getty)

“I think everything was magnificent. People were nice to us since we landed,” he said after the first-leg, which ended 1-1.