Canadian Eugenie Bouchard survived a scare from a 431st-ranked challenger from China on Monday to reach the second round of the Australian Open, scoring a 7-5, 6-1 victory over Chen Tang Hao.

Bouchard, the 30th seed from Montreal, rode a roller-coaster in the one-hour opening set after earning a 3-1 lead, only to lose it a game later on a double-fault to her neophyte opponent.

Bouchard, recently named The Canadian Press Female Athlete of the Year, was broken again to drop to 3-4 as Tang rifled back a return winner before holding for a 5-3 lead.

Bouchard saved set points in the ensuing game on Tang errors before finally earning a 7-5 win on a break.

The 19-year-old Bouchard was more in control in the second set and dominated to win the set 6-1.

Eugenie Bouchard

Canada's Eugenie Bouchard serves during her women's singles match against China's Tang Hao Chen on day one of the 2014 Australian Open in Melbourne on Monday. (William West/AFP/Getty Images)

"It was really fun, I had some good support, it was good atmosphere," but admitted that the 35 degree heat was a challenge.

"It was hotter than past few days, tough for both of us. It's strange training at one temperature [around 25 on Sunday] and playing in something completely different. But no complaints, it was the same for both of us.

"I'm big on sunscreen and hydration, especially the night before. I did a good job of it and was fine. I'd rather play tennis in the sun than do anything else anyway."

Pospisil moves on

Vasek Pospisil, a 23-year-old Vancouver resident who grew up in Vernon, B.C., is ranked 28th. He eliminated Australian Sam Groth with a 6-4, 6-3, 6-4 win.

Pospisil, 23, was never troubled by Groth and appears to have overcome a back problem which bothered him this month in India and Sydney.

In the second round, Pospisil will face another Australian in Matthew Ebden, who beat Nicolas Mahut of France 6-3, 7-5, 4-6, 0-6, 6-3.

Pospisil said that while he did not feel at 100 per cent, he played well.

"I played surprising well, I was not expecting to play like this," he said. "I wasn't feeling that great and only played points the day before, I didn't have much preparation.

"But I returned and served well, overall I did fine."

"I didn't feel any fatigue, I was playing relaxed because of my back," he added. "I don't anticipate any problems in the next round but I'm glad I didn't have to go five sets."

Pospisil overcame 16 aces from his opponent, firing six of his own and breaking on four of 10 chances. He scored 31 winners and 17 unforced errors.

The Canadian earned the break he needed in the seventh game of the opening set and in the final game of the match on the Groth double-fault.

Venus Williams falls in 1st round

Just as she was starting to show glimpses of returning to form, Venus Williams was let down by her serve and her concentration at crucial times and lost 2-6, 6-4, 6-4 to Ekaterina Makarova.

The No. 22-seeded Makarova upset Serena Williams in the fourth round here in 2012, but was comprehensively outplayed in the first set against the elder of the Williams sisters on Monday, dropping serve three times.

Williams had chances in the second set, too, missing a break-point opportunity to go up 4-2, and then serving three consecutive double-faults after leading the ninth game 40-30 to surrender a crucial break.

The 33-year-old Williams, the second-oldest player in the tournament and a seven-time Grand Slam singles champion, took some time out after the second set to change her zebra-striped dress and came back strongly, taking a 3-0 lead. But Makarova rallied again and Williams' error count rose — she had 21 of her 56 unforced errors in the deciding set.

She has struggled with injuries and illness in recent seasons but reached the final of the WTA event at Auckland to open the year and said after arriving at Melbourne Park that she was feeling better than she had in years.

"The last 12 months I have had issues, but this year I definitely am looking forward to having a good run and feeling well."

That didn't happen Monday.

"My level was a little bit too up and down. Obviously my error count was a little high," Williams said. "I have to give her a lot of credit, though, she was very determined ... played hard."

It was only the second time in 14 appearances that Williams lost in the first round at the Australian Open, where her best run remains a loss to her sister in the 2003 final.

"It was a really tough match to play someone like Venus in the first round, she is such a great player," Makarova said. "At 3-0 down [in the final set], I decided I had to fight for every point. I just kept fighting and I turned around the match."

Makarova will meet another American in the second round after qualifier Irina Falconi beat Anabel Medina Garrigues of Spain 6-3, 6-1.

Li Na advances

Two-time finalist Li Na beating Ana Konjuh of Croatia — the youngest player in the tournament — 6-2, 6-0 in 61 minutes to set up a meeting with another 16-year-old in the next round after Belinda Bencic of Switzerland accounted for 43-year-old Japanese veteran Kimiko Date-Krumm in three sets. Date-Krumm was 27 years older than Bencic, the reigning French Open and Wimbledon junior champion.

The 2011 French Open champion, who lost finals at Melbourne Park to Victoria Azarenka last year and Kim Clijsters in 2011, says the Australian Open "is my favourite Grand Slam." She's in the same half of the draw as No. 1-ranked Serena Williams, who was scheduled to play a night match against Australian teenager Ashleigh Barty.

Wimbledon semifinalist Kirsten Flipkens was the first woman into the second round when she beat Britain's Laura Robson 6-3, 6-0. No. 9 Angelique Kerber, No. 14 Ana Ivanovic, No. 28 Flavia Pennetta, Bouchard and No. 31 Daniela Hantuchova also went through.

Eighth-seeded Stanislas Wawrinka, who won the recent Chennai Open in India, was the first man into the next round, advancing after just 15 games when Andrey Golubev retired with an injured left leg.

Wawrinka, who lost 12-10 in the fifth set to eventual champion Novak Djokovic in the fourth round here last year in the longest Grand Slam match of 2013, was leading 6-4, 6-1 when his Kazakhstan rival quit.

Third-ranked David Ferrer opened with a 6-3, 6-4, 6-4 win over Colombia's Alejandro Gonzalez on Rod Laver Arena and No. 7 Tomas Berdych beat Aleksandr Nedovyesov of Ukraine 6-3, 6-4, 6-3.

Other men advancing included No. 9 Richard Gasquet, No. 14 Mikhail Youzhny, No. 32 Ivan Dodig, who beat fellow Croatian Ivo Karlovic 7-6 (8), 6-3, 7-6 (4), and American Sam Querrey, who defeated Santiago Giraldo of Colombia, 6-3, 6-2, 3-6, 7-6 (3).

"To win this match, in a tiebreak in the fourth set, gives me a ton of confidence," said Querrey, who had 47 winners and 24 aces.

With files from The Associated Press