It was Rashford's second goal in as many games following a barren run of matches that saw him go 11 without scoring.

"Marcus is one of the top strikers in England and has everything you need for a modern forward -- pace, skills, size and physicality," said Rangnick.

"In the end it is all about confidence and I am pretty sure those two goals will have raised his confidence. It's now about him taking the right steps and continuing. I think he will play an important role for the rest of the season."

The 24-year-old Rashford finished off a slick team move with the last play of the game, tapping home from Edinson Cavani's low cross. The 1-0 win lifted United into fourth with 38 points from 22 games.

Asked if "Fergie Time" was now "Ralfie Time", Rangnick added: "I don't know how long 'Fergie Time' was. Was that the last five minutes? I wouldn't mind if that happened.

"But we would also like to have more games like Brentford when we were 3-0 up. But if you score in the last seconds the big advantage is there is no time for the team to reply."

United next host Middlesbrough in the fourth round of the FA Cup on Feb. 4.