Sadly, African teams are struggling in the 2010 World Cup. It doesn't help that a number of key African stars are injured, but it also doesn't help when players make stupid mistakes. The red card changed the game and Greece was able to get back into and eventually win the game.
Kaita kicks out after a player from Greece pushes him near the sidelines and earns a straight red. Perhaps this should have just been a yellow card, as Kaita didn't really connect with the his kick, it was more frustration than anything, but the referee can't allow for this.