VANCOUVER, July 6 : Switzerland coach Murat Yakin faces an anxious wait to see if three of his most influential players will be fit for their World Cup last-16 clash with Colombia on Tuesday.Forwards Johan Manzambi and Ruben Vargas quit training early on Monday along with midfielder Djibril Sow, and the team said they would make a further statement about their fitness if there was any risk that they would not be able to play in the game in Vancouver. "Obviously, if they have to quit the training session earlier, everybody is very annoyed because this is going to be a very big loss. If they might not play tomorrow, it could be a huge issue for us," coach Murat Yakin told a news conference."We will see what happens this afternoon, because they will go through some medical examinations, but t