The Paris Masters was blown wide open when both Rafael Nadal and Roger Federer pulled out of their quarter-finals with injuries.
Second seeded Federer was the first to go on Friday, announcing that he would not be able to take his place on the centre court as planned this evening against James Blake.
Top seed Nadal did see some action shortly afterwards but promptly withdrew with an injury to his right knee after dropping the first set 1-6 to Russia's Nikolay Davydenko.
It was a double body blow for the prestigious tournament, which has been hit by a rash of injury withdrawals in recent years.
In the day's opening quarter-final, Andy Murray's hopes of making tennis history by winning three consecutive Masters Series titles were wrecked by an outstanding David Nalbandian.
The defending champion from Argentina won their quarter-final tie 7-6 (7/3), 6-3 producing the best tennis of the week as his love affair with Paris in the autumn continued.
The shocks of the day, however, concerned Federer and Nadal who had been seeded to face off in Sunday's final in what would have been their first meeting on court since their epic Wimbledon clash in July.
The second seed, who has never won a tournament in Paris, strained his back going for a shot in his opening match on Wednesday against Sweden's Robin Soderling and it came back overnight on Thursday to haunt him.
It was the first time in his career that Federer had been forced to withdraw from a tournament after it had started and it will cast doubts over whether he will be able to defend his Masters title in Shanghai starting in nine days time.