The youngster was introduced after 58 and immediately changed the game, rounding off a mesmerising run with a pin-point assist for Juan Mata.
He continued to cause problems on the left hand side with his mazy, unstoppable running power as Jose Mourinho‘s men cruised to a comfortable 2-0 win.
Neville, speaking on Sky Sports after the game, was quick to highlight the 19-year-old influence.
“The way in which he [Mourinho] deployed Rashford was the best thing,” he said.
“He held him on the touchline wide and it really did cause them massive problems.
“It’s an old rule that when you’re playing against ten-men you have to make the pitch big as possible.
“Mkhitaryan and Lingard they were coming in too narrow, too deep and too early. But when Rashford came on, he just hung out on that touchline and he really made it difficult. His influence on the game was really big, he created a lot of chances for Manchester United.”
This was a truly exhausting affair for West Ham. 48 hours after defeat against Leicester City, they had to spend 75 minutes chasing after Mourinho’s men.
Right back Havard Nordveit, who played 90 minutes on Saturday, did well to contain Jesse Lingard and Henrikh Mkhitaryan, inviting them to push infield and closing space as a result for 60 minutes.
Rashford’s presence, however, was simply too much: the youngster’s raw speed and fearlessness going forward created problems from the first time he picked up the ball. Mourinho told the Englishman to stay wide and it paid dividends – the pitch suddenly grew twice in size and West Ham, for all their efforts, just couldn’t cope with the teenager.