The Busby Babe spent seven years playing for the Red Devils between 1950 and 1957 before going on to enjoy nine years with Nottingham Forest.
However the 89-year-old clearly wasn't impressed by what he saw as Erik ten Hag's side struggled throughout.
The first half was a dour affair between the two sides, with the start of the second half not much better.
Nicolas Dominguez ignited the game by giving Forest the lead after 64 minutes, with Man United failing to get themselves going.
It was then that Whitefoot was pictured in dreamland in the stands, with Man United only recording two shots at that point.
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However Marcus Rashford leveled the game for the Red Devils to ignite the contest, leading Erik ten Hag's side to push forward to go for a winner.
But it was Morgan Gibbs-White who got the last laugh by making it 2-1 for Nuno Espirito Santo's side, who saw out a memorable victory.
For Man United, Whitefoot's expression was symbolic of their performances of late, with only Sheffield United and Burnley scoring fewer goals in the Premier League this term.