Melbourne, Australia ? Top-seeded Maria Sharapova narrowly avoided a stunning third-set collapse, overcoming the soaring heat and her own mistakes to beat Camille Pin, 6-3, 4-6, 9-7, early today in the first round of the Australian Open.

The heat – it was 97 degrees and muggy at midday – forced tournament officials to suspend play on the outside courts.

The Extreme Heat Policy, which measures conditions by combining the air and court surface temperatures, was invoked halfway through the Sharapova-Pin match.

That meant that the roofs at Rod Laver Arena and the other main show arena were to be closed at the completion of ongoing matches. Current matches on outside courts were allowed to finish, but no new matches were allowed to start for at least three hours.

Eighth-seeded David Nalbandian grew stronger in the heat as Janko Tipsarevic wilted. Tipsarevic retired because of heat exhaustion in the fifth set more than 90 minutes after he wasted his chance at serving for the match.

Nalbandian, the 2002 Wimbledon finalist and a semifinalist here last year, won, 6-7 (5), 4-6, 7-6 (2), 6-0, 2-1.