Andy Murray is out of the ATP World Tour Finals even though he won his latest game, against Fernando Verdasco.
Murray beat Verdasco on Thursday, but had to wait for a later match to find out if he was in the semi-finals.
Sadly for Murray that later match didn't go his way, when Juan Martin del Potro defeated Roger Federer.
Murray, Federer and Del Potro all won two of their three group matches, but after some difficult maths, it was Murray who was knocked out.
As well as the same number of match wins all three players had also won the same number of sets too.
That meant officials started counting up the number of total games the players had won and lost in their three group matches, and Murray missed out by a single game.
Had Murray won his earlier game in straight sets he'd have gone through, but he needed three sets to get past Verdasco, 6-4 6-7 7-6.