China's Li Na led the march into the Australian Open second round on Monday but former great Venus Williams and seventh seed Sara Errani crashed out in the Melbourne heat.
Venus Williams reacts during a match against Ekaterina Makarova on day one of the 2014 Australian Open tennis tournament in Melbourne on January 13, 2014
Charismatic fourth seed Li demolished junior champion Ana Konjuh 6-2, 6-0, handing the 16-year-old a tennis lesson as she sets about ending her tournament jinx.
Li has made the final at Melbourne Park twice before, leading both times before being overcome by Kim Clijsters in 2011 and Victoria Azarenka last year, and she is determined to go one better this time round.
"I always love coming to Melbourne." she said. "I'm feeling good and feeling healthy."
Her easy win set up a second-round clash with another qualifier in Swiss Belinda Bencic, who beat 43-year-old Japanese veteran Kimiko Date-Krumm, 27 years her senior, in three sets.
Li is in line to meet world number one Serena Williams in the semi-finals, with the five-time Melbourne champion getting her campaign underway Monday evening against Australian youngster Ashleigh Barty.
Defending champion Azarenka plays on Tuesday.
Also through was Germany's ninth seed Angelique Kerber, who had a second-set wipeout before bouncing back to overcome Australian Jarmila Gajosova 6-3, 0-6, 6-2.
Former world number one Ana Ivanovic and local hope Samantha Stosur also safely booked their second round berths.
But Italy's Errani became the highest seeded casualty when she slumped to Germany's Julia Goerges 6-3, 6-2.
It was also curtains for seven-time Grand Slam champion Venus Williams, who fell in a marathon clash against Russian 22nd seed Ekaterina Makarova.
Williams was unseeded despite playing 11 events last year and making three semi-finals, and she looked on course for victory after winning the first set.
But a series of unforced errors and failure to convert crucial break points cost her dearly and she was sent packing 2-6, 6-4, 6-4 after a nearly two-and-half-hour epic.
"Obviously losing any match is never any fun, especially in a major. So definitely would have wanted a different result," said Williams.
"I think my error count was a little high. I haven't looked at the stats yet, so I don't know what the errors were or the first‑serve percentage was. I have to look at that and just kind of evaluate the match."
Williams hasn't won a Grand Slam since Wimbledon in 2008 and is without a title since Luxembourg in October 2012, although she made the final of this month's Auckland International, losing to Ivanovic.
The American suffers from the energy-sapping Sjogren's Syndrome and she appeared to wilt in the hot conditions as the match wore on.
After showing some glimpses of the Williams of old in the first set with some sizzling backhand winners, she blew a chance to go 5-2 up in the second by failing to convert two break points.
It cost her dearly with Makarova bouncing back to take the set and ultimately the match to line up a second round clash with American Irina Falconi, who beat Spain's Anabel Medina Garrigues.
In contrast, Li was always in charge against Kunjoh, who was making her Grand Slam debut after winning the Australian Open girls' title last year.
Li rattled through the match, giving the teenager a lesson and escaping the court with minimum effort as temperatures climbed to 30 Celsius (86 Fahrenheit), with 40-plus Celsius forecast on Tuesday.
It was an impressive start for Li, who reached the season-ending WTA Championships final last year and started 2014 with victory at the Shenzhen Open.
But she would not have been competing at all if she had gone through with a threat to quit last year.
The charismatic Chinese told the Melbourne Age that she almost didn't play Wimbledon and considered retirement after a second-round defeat at Roland Garros and a quarter-final loss at Eastbourne, which forced her to consider retirement.