In less than two months the 18-year-old has gone from unknown academy player to become one of the most feted young footballers in English football.
Handed a surprise debut when Anthony Martial sustained an injury warming up for the Europa League clash with FC Midtjylland, Rashford certainly grasped that opportunity and followed up a brace in that tie with another double against Arsenal days later.
The teenager has shown no sign of letting up and marked his 12th senior appearance with a seventh goal on Saturday, securing a 1-0 win that relegated Aston Villa and earned praise from team-mate De Gea.
"It's unbelievable, no?" he said. "This player is really young and he's scored many goals.
"Hopefully, for many years, he'll be in this club and can make history for the club as well. He's a shy guy, he is a really good lad and a good team-mate. He's a really good guy."
Rashford's first-time strike settled an uninspiring clash at Old Trafford, where the gallows humour of Villa's travelling support was the main entertainment.
De Gea knows it was not the most entertaining encounter for supporters but an important victory on the back of the FA Cup quarter-final replay at West Ham.
"I think we didn't play really well but sometimes you have to win the games like this, take the three points and think to the next game," he told MUTV.
"Always we try to put everything on the pitch, give everything - every game we do the same.
"We take the three points and think quickly of the next game.
"I think we've defended really well this season and we need to continue until the last game and hopefully we will be in the top four.
"We need to win our games and wait for the rest of the teams. We will see in the end."
Source: PA