Dutchman Frank de Boer said it was a "pity" the 20-year-old Rashford played under the Portuguese.
Manchester United boss Jose Mourinho has slammed Frank de Boer over comments the former Crystal Palace manager made about striker Marcus Rashford.
De Boer said it was a "pity" the 20-year-old, who scored both goals in United's 2-1 victory over Liverpool on Saturday, played under the Portuguese.
The Dutchman's remarks prompted a savage response from Mourinho.
"I read something, some quote from the worst manager in the history of the premier league, Frank de Boer, seven matches, seven defeats, zero goals. Where he was saying that it is not good for Marcus Rashford to have a coach like me because the most important thing for me is to win. If he was coached by Frank, he would learn how to lose."
Meanwhile, Man Utd's French forward Anthony Martial is fit for the club's Champions League round 16, second-leg, game at home to Sevilla.