The French midfielder was arguably United's best player and, after the game, his manager said he was at the same level as Barcelona's and Real Madrid's top stars, though he admitted that the Spanish giants were, overall, ahead of United.

"[Lionel] Messi and Neymar, there is only one; there is not two. [Luis] Suarez, [Andres] Iniesta, [Gerard] Pique, [Cristiano] Ronaldo, [Gareth] Bale, [Luka] Modric, Toni Kroos; there is only one so they can only play for one club, not for two clubs.

"We can't have them; they belong to the clubs. But I have to say that one of my players today, Paul Pogba; he showed the level, he showed he belongs to that level."

Neymar's 32nd-minute goal, which gave Barcelona the win, came about following slack play at the back from United. Mourinho admitted "we didn't defend well" but also said that his side should not be compared to Barcelona and Real Madrid, both of whom United have faced in the last four days.

"We prefer to compare us with the teams we play in the Premier League and we are much more adapted to that very hard competition," said Mourinho. "It is a different competition with different style, different kind of player. I think, in this moment, the best players are in [Real Madrid and Barcelona] and you have to accept that as a reality.

"For us to play them in preseason without any kind of pressure and without being worried about a result was very good for us because both play with their best team. I think only Pique was on the bench [for Barcelona], I think only Ronaldo and [Sergio] Ramos didn't play [for Madrid] so it's very good for us to measure ourselves against them."

United face Madrid in the UEFA Super Cup on Aug. 8 and, with their return to the Champions League next season, the possibility exists that they could meet one or both of the Liga giants again. Without the same ability as the very best opponents, Mourinho said that there are different ways to be successful.

Mourinho said: "What you can do when the matches are real matches you try to compensate the difference in quality with a certain tactical organisation? With that you can win; in football it is possible that a team is, in a certain day, better than the sum of the parts.

"But the parts [of Barcelona and Real Madrid] are amazing. The relation with the ball is amazing. You can argue about occupation of space and tactics and compact blocks but the relation with the ball is still the most important thing.

"As an opponent on the bench like I am it is beautiful to see a few guys their relation with the ball."

Mourinho's squad return to England having won three of their five games in the U.S., with one draw and one defeat. United face Norwegian side Valerenga in Oslo on Sunday.