Jose Mourinho told Paul Pobga he must match the mentality of his Manchester United team-mates after he watched the 4-1 Premier League win over Fulham from the bench.
Substitute Aboubakar Kamara converted a 67th-minute penalty to give Fulham faint hope that was almost instantly snuffed out as Andre-Frank Zambo Anguissa collected a second yellow card for a foul on Marcus Rashford, who completed the scoring.
Fred, the sparingly used £52million recruit was on in midfield ahead of Pobga by that stage, but Mourinho told a post-match news conference the French World Cup winner will have his chance to impress in the midweek Champions League trip to Valencia.
"He has to play with the same mentality as the team is playing," the United boss said.
"Paul can be a fantastic player, he has the potential to be a fantastic player.
"Against Valencia he is going to start and have a fantastic football game to play and to show everybody how good he is."
United midfielders Nemanja Matic and Ander Herrera were praised by Mourinho for their pressing against Claudio Ranieri's struggling side – areas of the game generally not counted among Pogba's strengths.
Lukaku similarly found himself on the bench for the midweek draw against Arsenal but ended a run of 997 minutes without a goal at Old Trafford.
"Romelu's performance improved a lot in relation to previous matches, the way he was pressing, fighting for the team," Mourinho added.
"The team was good, not so much in the second half but in the first half [Phil] Jones and [Chris] Smalling brought the team up, we were a compact unit that gave no chance to Fulham in the first half."