Zlatan Ibrahimovic's starring role in Manchester United's EFL Cup win is proof to his doubters that he could succeed on Mars or the moon - let alone the Premier League - says agent Mino Riola.
The Swede bagged a brace to fire Jose Mourinho's men to a 3-2 triumph over Southampton at Wembley on Saturday, ensuring the Red Devils lifted their first piece of silverware this season.
The cup also represents Ibrahimovic's first title secured on English soil, a matter of months after the 35-year-old moved to Old Trafford on a free from Paris Saint-Germain.
"He won a lot of things but for me also this [the EFL Cup triumph] was a special cup because of the disbelief the Premier League has always shown him before he came here, so this was a special victory," he told talkSPORT.
"It was one of those challenges we wanted to take because he could have easily gone for more money or for other clubs but one of those challenges was let's go to the Premier League and prove that he can get goals in the Premier League.
"I did not have one minute of doubt that he could but a lot of people in the Premier League or around England had these doubts. I don't think anyone sane in mind still has these doubts, but you never know!"
Raiola also expressed his surprise that it took so long for Ibrahimovic to come to England.
"There was a lot of clubs in England that had reservations about if he could do the same there and I was always a little bit stunned by that question, that doubt, because in England pace is so important – maybe one of the most important attributes of the Premier League," he said.
"I don't know if they doubted him because of pace or quality, actually that is a question you should ask others. I was never in doubt. If he could do it wherever he did it and knowing how he is and what kind of man he is on and off the pitch, he can do it anywhere. He is the only player in the world who can be successful on Mars or on the moon."
Asked if there had been interest from England previously, Raiola said: "Not at the level that he wanted. Also it was difficult as there was never momentum to do it. He was never a free agent in his career because he has always had top clubs wanting him. For an example my big name Alex Ferguson never asked for him.
"It is difficult to find someone with his mental determination, mental force, physical force, technical skills all in one.
"For years I have said he is the best because from all the top players that are still in the game there is nobody so complete, nobody who did it at all levels at different clubs.
"For all respect to everyone else, to spend 10 to 15 years in the same club is different to going to a club, adjusting yourself and doing it again. He is able to do that."