Wilder, 34, was dominated last February as he surrendered his WBC title to Fury, 31, after two knockdowns and seven rounds of defeat.
Afterwards, retired Mayweather – who has taken up coaching – announced his desire to train the Bronze Bomber to avenge defeat.
But Fury has warned the 43-year-old not to bother.
He tweeted: “No matter what you teach him, I will smash him.”
Mayweather toured the UK in February and was asked how Wilder could possibly win back the heavyweight title.
He responded: “If I train him. If I train him I can teach him how to win.”
Wilder was due to get his crack at revenge this summer but the coronavirus pandemic pushed back the heavyweight headliner.
Fury’s first WBC title defence then looked set for December, but without fans able to attend promoter Bob Arum admitted it could be backdated to 2021.
But that does not suit the Gypsy King, who has told his UK matchmaker Frank Warren to find him another opponent on home soil to keep busy.