The mood of those Manchester United fans watching the game against Arsenal when that red card was brandished to Paul Pogba suddenly changed from a gleeful one to a rather dreary one, despite their team triumphing at the home of a rival by an incredible 1-3 scoreline.
And the reason wasn't far fetched, given how influential the French star has been this season for United, and even more, in the game at the Emirates, notching two assists.
But having said all that, there are ways United can profit from having Pogba miss the match against Manchester City on Sunday.
City will come into the game under more pressure to win
United, trailing City by eight points, should have been the side under more pressure to win; playing at Old Trafford, heading into the clash. But with the Red Devils now set to play the game without the services of their midfield linchpin, Pep Guardiola and his side will be under some sort of pressure to win this one over their city rivals - presenting Jose Mourinho's United something to capitalise on.
Chance for other United players to stake their claim in the team
Often we have seen fringe players in a team stake their claims with opportunity like this, and this should come as an opportunity for other players that have been sidelined to come out with something to prove to the manager. Marcus Rashford would probably still be scampering around United's reserves had it not been for injuries to Wayne Rooney, Anthony Martial and Will Keane.
The then 18-year-old took the opportunity by the scruff of the neck; after an injury to Anthony Martial in the warm-up to an Europa League round of 32 clash against Midtjylland, scoring two goals in the second half of a 5-1 United win. And also went on to score two against Arsenal in his Premier League debut, and then scored the only goal in the Manchester derby, making him the youngest ever scorer in a Manchester derby in the Premier League era.
Sunday's derby game will present the likes of Ander Herrera, Delay Blind and young Scott McTominay the chance to prove their worth if selected by the manager, which can also influence the game positively for United, as we saw with Rashford.
Pogba's lack of defensive nous won't be risked
Pogba might be the powerhouse of United's midfield (especially going forward, linking the midfield with attack, and orchestrating most United's offensive moves), but his lack of the necessary defensive qualities as a central midfielder can be a problem to any side.
And against a side like City who would be looking to punish United for the slightest of gaffes in midfield, United can go into the clash assured of a better defensive covering in midfield with the likes of Herrera and Blind.
United might not offer much going forward with the absence of Pogba, but they won't risk much in midfield defending against the likes of David Silva, Kevin De Bruyne and Fernandinho on Sunday.