Martial came off the bench in the second half, replacing Rashford in the 70th minute at Old Trafford before netting the vital winner in the 81st minute to hand Manchester United all three points.
Lukaku played for the full 90 minutes at Old Trafford as he continues to hold down a regular place in the first team since his move from Everton in the summer transfer window.
And Mourinho was delighted by the trio’s performances as Manchester United returned to winning ways in the Premier League on Saturday against Spurs.
Speaking to Sky Sports after the game, Mourinho said: “Sometimes he [Martial] starts the match and his contribution is good, but not scoring so many times as he does coming from the bench.
“But he’s playing well – the same as Rashford, the same as Lukaku.”
The win left Manchester United five points behind leaders Manchester City after 10 games of the new season.
The Red Devils return to Champions League action on Tuesday night when they host Benfica at Old Trafford.
Mourinho’s men have made a fine start in Europe this season, winning all three of their opening Champions League games so far.
The Red Devils are aiming to win the title this season after their sixth-placed finish last term.
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