Ole Gunnar Solskjaer says Fred's performance in Manchester United's stunning 3-1 victory over PSG was his 'breakthrough' for the club.
The Brazil midfielder played all 90 minutes in United's win, which saw them score a last-minute penalty to secure passage to the quarter-finals of the Champions League on away goals.
Fred has struggled to make an impact for United since arriving from Shakhtar Donetsk for a fee Sky Sports News understands to have been over £50m, but caretaker boss Solskjaer believes Wednesday night in the Parc des Princes was a turning point for the 26-year-old.
He said: "Fred - that was probably his breakthrough for us. You can see why we've signed him.
"He's got the mentality of a Brazilian international - he is a Brazilian international.
Live Renault Super Sunday
"He gets on the ball, no fear, no doubt whatsoever. We played a system today that he used to play at Shakhtar."
Solskjaer was also fulsome in his praise of Romelu Lukaku, who scored twice against PSG to take his tally to six goals in his last three games for United.
The Belgian striker had scored just nine goals in 34 games for his club before that run, but Solskjaer said: "Six goals in three games - not bad!
"Ever since I came, he's worked his absolute socks off to get fitter and to get into the team. I love strikers who want to score goals. In training, he practices every day.
"He's had his criticism but we've played him now in a position that suits him more - more direct, facing the goal. I'm delighted for him because he's a great lad."