The home side sprang out of the blocks at Old Trafford and were the better side in the opening half hour.
Rashford’s enthusiasm spread throughout the team as United pressed Arsenal into regularly giving the ball away.
The striker didn’t manage to get on the scoresheet but he showed a willingness to work hard all over the pitch.
And his overall display caused former Liverpool star Danny Murphy to praise the England international on Match of the Day last night.
“If you just go back to the Southampton game at the weekend, they started poorly,” he said on Match of the Day.
“It was lackadaisical with lethargic mistakes. But this was a different United team.
“Rashford set the tone for the front and Herrera was fantastic in midfield.
“But they were all at it and it wasn’t just for 10 or 20 minutes, it was the whole game.
“Just look at the difference at the start of the game. It gets the fans onside and creates an atmosphere.
“If it starts at the front, usually the players behind follow.
“And Rashford today was fantastic again. I pick him out at the weekend.
“His willingness to work with and without the ball is excellent as was Herrera’s as well.”
Herrera reacted first when Bernd Leno palmed Marcos Rojo’s free-kick away in the first half.
The Spaniard looked to be offside when the kick was taken but he managed to cut the ball back for Anthony Martial to score.
Murphy admitted he is surprised that the former Athletic Bilbao star doesn’t see more action under Jose Mourinho.
“I find it amazing that he doesn’t play more games,” he added. “Because he is their one player who can get about.”