The United manager left Pogba out of his starting line-up for the second time this week as his side recorded their biggest victory in 13 months, 4-1 over last-placed Fulham.
But the absence of Pogba remains a hot issue for Mourinho who has complained about his inability to compete with Manchester City and Chelsea in the transfer market only to leave his record signing on the bench.
"He has to play with the same mentality as the team is playing," said Mourinho when asked how Pogba can win back his place.
"Paul can be a fantastic player. He has the potential to be a fantastic player and against Valencia (on Wednesday) he's going to start.
"Against Valencia he is going to have a fantastic football game to play in and show everybody how good he is."
In Pogba's absence United made an electrifying start with three goals in the first half.
After 13 minutes, Ashley Young received a short pass from Marcus Rashford and beat Denis Odoi far too easily as he cut into the Fulham area before curling the ball into the top corner.
The second goal, after 28 minutes, came on the counter-attack as Romelu Lukaku slipped the ball to Rashford who picked out Juan Mata, arriving speedily into the Fulham area, with a perfect pass which his Spanish team-mate steered left-footed into the corner.
There was time for United to add a third after 41 minutes, from a clever corner routine that saw Mata and Jesse Lingard exchange passes before the former crossed into an empty six-yard area where Lukaku gratefully converted the easiest of chances.
Red card frustrates Fulham
Veteran manager Claudio Ranieri made two half-time changes and one of his substitutes, Aboubakar Kamara, pulled a goal back from a 67th minute penalty, awarded after Ander Herrera was judged to have tripped him.
But Fulham's hopes of a comeback were short-lived as within a minute Andre-Frank Zambo Anguissa was sent off for a second bookable offence, for a foul on Rashford.
"I watched on video and my player touched only the ball and the referee gave a second yellow card," said Ranieri.
"At that time it changed the game because from the first minute of the second half we were much better and showed what we have to do to stay in the Premier League."
Down to 10 men, Fulham were susceptible to more United attacks with Lukaku and Rashford missing glorious openings before the latter completed the rout on 82 minutes.
Rashford beat Sergio Rico at his near post with a curling shot from just inside the area and had substitute Scott McTominay succeeded in converting a header two minutes later, United would have scored five goals for the first time since Alex Ferguson retired five and a half years ago.
"A good result, good performance, individual performances, Lukaku and Rashford - no goals for a while, even their goals mean something for them too," said Mourinho.
"The spirit, the team was there to win and give everything and when you give everything nobody can point the finger at you.
"But what I really want is not a single United fan point the finger at us by saying we do not give everything. It is the type of performance that people respect the effort."