A tale of two Opens as tempers rise

Heat starting to wear thin on stars at year's first Grand Slam event

Maria Sharapova toiled in 43 C temperatures for more than 3 1/2 hours on Rod Laver Arena. Next up, Caroline Wozniacki played in what she considered "pleasant" and nearly room-temperature conditions under the roof on the same court at the Australian Open.

Rafael Nadal and Roger Federer also played on Thursday - unusually simultaneously - in the more comfortable conditions after the tournament invoked its Extreme Heat Policy and the roofs on its two main arenas were closed. All matches on outside courts, meanwhile, were suspended for more than four hours until temperatures dropped.