Six-time Australian Open champion Serena Williams progressed to the second round with a straight-set win over Swiss teenager Belinda Bencic.
The American, 35, won 6-4 6-3 in 79 minutes against the 19-year-old in scorching conditions in Melbourne.
The world number two, who is chasing a record 23rd singles Grand Slam title, said she “has nothing to lose”.
“Every match I’m playing for fun. I get to travel the world and do what I do best – play tennis,” she added.
Williams lost the Australian Open final last year to Angelique Kerber but won Wimbledon to equal Steffi Graf’s Open era mark of 22 Grand Slam singles titles.
She has barely played since the US Open last September because of injury, and lost in the second round of this month’s Auckland Classic, but eased doubts about her form and fitness with a typically powerful performance in temperatures of around 35C.
Source: BBC Sports