Roger Federer overcame stifling heat as his bid for a fifth Australian Open title began with a routine victory against James Duckworth.
The Swiss, 32, swept the Australian aside 6-4 6-4 6-2 and is joined in round two by Jo-Wilfried Tsonga, who beat Filippo Volandri 7-5 6-3 6-3.
Defending women’s champion Victoria Azarenka toiled but was too strong for Johanna Larsson, winning 7-6 6-2.
Former world number one Caroline Wozniacki also made it safely through.
The Dane beat Lourdes Dominguez Lino 6-0 6-2 in just 66 minutes.
It was a much less enjoyable day for John Isner, though, as the 13th seed retired injured from his match against Martin Klizan.
The American hurt his right ankle at the Hopman Cup exhibition event at the beginning of the year but won a tournament in Auckland, New Zealand, last week. However, he withdrew at 30-0 down in the third after losing the first two sets.
In the other match at the Rod Laver Arena Seppi (Ita) [24] beat Hewitt (Aus) 7-6 (7-4) 6-3 5-7 5-7 7-5
Hisense Arena
Wozniacki (Den) [10] beat Dominguez Lino (Spa) 6-0 6-2
Tsonga (Fra) [10] beat Volandri (Ita) 7-5 6-3 6-3
Radwanska (Pol) [5] beat Putintseva (Kaz) 6-0 5-7 6-2
Murray (GB) [4] beat Soeda (Jpn) 6-1 6-1 6-3
Match report
Margaret Court Arena
Halep (Rom) [11] beat Piter (Pol) 6-0 6-1
Cibulkova (Svk) [20] beat Schiavone (Ita) 6-3 6-4
Jankovic (Ser) [8] beat Doi (Jpn) 6-1 6-2
Del Potro (Arg) [5] beat Williams (US) 6-3 6-4 6-4
Harrison (US) v Monfils (Fra) [25]
Results Sourced from the BBC.