Jelena Jankovic, the World No1, is urging tennis shoe manufacturers to introduce an air-conditioning system to help the players combat the near 100˚F on court temperatures that turned the Australian Open into a test of stamina today.

While Jankovic's idea was delivered tounge in cheek, the heat being generated by the hard courts in Melboure are taking their toll, forcing her to put her shoes on ice during change-overs.

Jankovic, who beat Austria's Yvonne Meusburger 6-1, 6-3, explained: "Really, it's like fire in the soles of my shoes. My feet were burning and the soles of my shoes got so hot I was putting my feet on ice to kind of cool them down.

"I will tell my shoe manufacturer to put some air-conditioning in there. With the technology growing and getting better, I believe in the future we will have these kinds of thing."

Jankovic was joined in the second round by fellow Serb and No5-seed Ana Ivanovic, who beat Germany's Julia Goerges 7-5, 6-3, and seventh-seed Vera Zonareva, of Russia, who won 7-6, 6-0 against Slovakia's Magdalena Rybarikova.