The promising young striker was drafted into Louis van Gaal’s side after Anthony Martial was injured in the warm-up ahead of the second leg of the Europa League last-32 tie at Old Trafford.
Rashford put United ahead on the night after Pione Sisto’s opener for the visitors was cancelled out by a Nikolay Bodurov own goal.
The 18-year-old forward extended the Red Devils’s third of the night before Ander Herrera and Memphis Depay sealed a 5-1 victory.
Former United striker Saha explained why he was impressed with Rashford following his memorable debut in the Europa League.
“His confidence to take the ball on,” Saha told ITV Sport.
“It was his debut but he showed great character by taking the ball. I liked his power and the speed. He has all the ammunition to be a dangerous striker.”
United were drawn against north-west derby rivals Liverpool in the Europa League last-16 draw on Friday afternoon.
The Red Devils host bitter rivals Arsenal in the Premier League at Old Trafford on Sunday afternoon.
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