The match was easily the most exciting of the competition thus far as both players halved the first two sets and then fought neck and neck in the third so that a tiebreak became inevitable.

In the tiebreak the 27-year-old Argentine, ranked 10th in the world, dug into his resources of mind and technique to snatch victory at 7-5 from Germany’s Schuettler, 29, who was among the top 10 in the world in the last two years.

Puerta disagreed with suggestions after the match that he was lucky to win, attributing his less than compelling play to a lack of familiarity with the surface. “This is only the third hardcourt tournament in my career and the first for the year,” said Puerta.

Asked how he would prepare for tomorrow’s semi-final, he said he would “sleep for for nine or ten hours and practise for 20 minutes” before the start. Clearly, Puerta was not going to lose any sleep over the identity of his opponent.

The day’s most authoritative quarter-final win belonged to No. 3 seed Radek Stepanek of the Czech Republic whose shrewd deployment of his serve and volley game overwhelmed the craft of Juan Monaco of Argentina 6-3, 6-4.

Stepanek sealed his win in the ninth game of the second set when be broke Monaco’s service, a splendid passing shot winning the game and then he held service to clinch the set and match.