Shakhtar Donetsk manager Paulo Fonseca, who worked with Fred for two seasons, has "no doubt" that Manchester United's Brazilian midfielder -- despite his difficult start at Old Trafford -- will "become one of the most important players in England."
"He's a big talent and he's still developing," he said, speaking exclusively to ESPN FC.
"I have no doubt he'll have a great future at Manchester United. But, of course, he needs time. It's totally different from what he was used to in Ukraine.
"He needs a period to adapt, to the club, to the league. It's a totally different situation."
Fonseca added that he believed Fred's natural position was as part of a midfield two in a 4-2-3-1, though the player, of course, could adapt to a three as well, as he's been doing thus far at Old Trafford.
"In my opinion his opinion is in a midfield two as the more attacking of two central midfield players," he said.
"He is physically strong and mobile, with the quality to build play, but he is also very good at breaking from midfield and gong to either side of the attack."
Fonseca's Shakhtar Donetsk travel to the Etihad to take on Manchester City on Wednesday, while Fred's Manchester United are in Turin against Juventus.