In the opening match of United's Champions League group stage campaign they secured an impressive 2-1 away victory at PSG, with Rashford scoring the winning goal three minutes from time with a precise finish in off the post.
It was a deserved goal for the Englishman, who, along with Anthony Martial, terrorised the PSG backline with his pace and movement in behind.
The plaudits came flooding in for him after the game, with Ferdinand saying he has the potential to be world class.
However, he would like Rashford to become "obsessed" with scoring goals, and compared him to a young Wayne Rooney who would eventually become a great goalscorer as well as a scorer of great goals.
"Rashford can definitely be world class if he keeps improving," Ferdinand said on BT Sport.
"He needs to add that poacher's element to his game. When Wayne Rooney signed for United he scored outrageous goals, he didn't score ugly goals. He became obsessed with scoring.
"Marcus scores fantastic goals and creates fantastic goals - if he can create that ugly side to the game then this kid can be unbelievable."
Ferdinand went on to highlight the current difference between Rashford and Mbappe.
"The difference between Rashford and Mbappe is when Mbappe gets the ball I'm on the edge of my seat because he shapes up to go for goal," he added.
"Marcus will have a look up and think about it a bit more."
Rashford has been praised for his work off the pitch as much as his work on it recently, as a month ago he was awarded an MBE for his continued charity work to fight against child poverty.