Manchester United were beaten 1-0 in the Champions League by Besiktas. It's the first time they've lost at home in 24 games.
The Premier League champions will still go through to the knockout stages of the competition despite the result.
Meanwhile Chelsea made sure they'd be top of their group with a 1-0 win against FC Porto.
Nicolas Anelka scored the only goal of the game, heading home a cross in the second half.
Earlier in the week, Liverpool and Rangers were knocked out of the competition.
Man United and Chelsea will join Arsenal who also qualified for the last 16.