The round-robin portion of the Tennis Masters Cup is over, and now the season-ending men's event has entered the knockout stage.

The semifinal line-up is complete, and it has been completed by Gaston Gaudio.  The mercurial Argentinian trailed Chile's Fernando Gonzalez for much of the match, and had to save three match points at 4-5 in the second set.  But once he had done so, he got right into the match, which got better and better as it went on.  The tennis was at times so entertaining that few in the Qi Zhong stadium wanted it to end.  But two rushes of blood to the Gonzalez head at 5-5, 30-30 in the final set cost him the match.  He hit a smash long after Gaudio had slipped, and then went for far too much on a second serve and double-faulted Gaudio the break, who served out a 1-6, 7-5, 7-5, victory.

"I was thinking the same thing as everybody here, that I was done," he said.  "I don't know how I came back, but finally I did it.  There were a lot of situations that were so emotional.  And it was fun for the crowd and not fun for me, but anyway, I am so happy about it."

Gaudio now plays Switzerland's top sportsman Roger Federer for a place in Sunday's best-of-five-sets final.  The other semi will be Nikolay Davydenko against David Nalbandian, with the possibility, though not likelihood, of an all-Argentinian final.