Venue: Melbourne Park Date: 18-31 January
Every Murray match live on BBC 1 or 2
Daily from 0830 GMT: live on BBC Red Button/website, 5 Live sports extra
Daily from 0000 GMT: text commentary on BBC Sport website
Henin admitted she had been nervous as she closed in on the win in the second set
Former champion Justine Henin defeated fifth seed Elena Dementieva 7-5 7-6 (8-6) in a thrilling encounter to reach the Australian Open third round.
The Belgian, who came out of retirement this month, twice served for the match before coming through in a tense tie-break after nearly three hours.
"It was a special night," said Henin. "That's why I probably came back on the tour, to live these kind of matches."
Henin's compatriot Kim Clijsters also went through, along with Dinara Safina.
Henin, playing her first Grand Slam event following a 20-month retirement, took the first set on her third set point.
Dementieva struck back in an error-strewn but pulsating second set to take a 4-2 lead but 2004 champion Henin took the next three games and then had a match point while serving for the match.
She was as good as she was before. She's a great player
Dementieva managed to force a tie-break but the Russian then netted a weak drop-shot to hand the Belgian another match point.
Former world number one Henin sealed victory with a volley to end a thrilling contest that had lasted two hours and 50 minutes on Rod Laver Arena.
"At the end the nerves got to me," a relieved Henin said. "It was really difficult to close the match out.
"In Brisbane [when she lost in the final to Clijsters] I got the opportunities and didn't take them, and I thought here it would be the same, so I am very happy.
"I couldn't believe I could live the emotions like that."
Dementieva, who had the misfortune to land near the unseeded Henin in the draw, said the Belgian is playing as well as she was before her retirement in May 2008.
"She was moving well and hitting hard. It just doesn't feel like she had the break," said the world number five.
"She was as good as she was before. She's a great player. Playing against her, you really can learn a lot and improve your game.
"We really need these kind of players to increase the level of the game, so it's great to have her back here on the tour."
Former world number one Henin will take on 27th seed Alisa Kleybanova, who earlier beat Sorana Cirstea, in the third round.
Clijsters, a possible quarter-final opponent for Henin,was always in control in a 6-3 6-3 win over world number 99 Tamarine Tanasugarn but could never totally dominate a determined opponent.
"I feel like I'm good enough on the day to beat my opponents," said the Belgian. "It's not my best tennis yet, but hopefully I can save that when it's really necessary."
Second seed Safina saw off Barbora Zahlavova Strycova 6-3 6-4 in the heat of the afternoon in Melbourne.
Last year's beaten finalist made 40 unforced errors, compared to her opponent's 31, but also hit 31 winners as she came through a scrappy match.
"In some moments I played not bad, but it's good that I won the match and still there is so much room to improve," said the Russian.
"That's such a good thing, you know deep inside you have so much more to bring out.
"I think the serve was pretty good today - and I won. In the next match I can do a little bit more and more."
In Wednesday's early matches there were no problems for the top women in action, although third seed Svetlana Kuznetsova was some way off her best despite the convincing 6-2 6-2 scoreline against Anastasia Pavlyuchenkova on Rod Laver Arena.
"I have played for plenty of years already in Grand Slams and even though I'm 24, it feels like I've been here for a while," said the French Open champion.
"I just get extra motivation when I play Slams, this is for what I work for, what I play for. You just enjoy it so much."
Fourth seed Caroline Wozniacki was made to work hard in the first set before easing past Aleksandra Wozniak 6-4 6-2 on Hisense Arena.
"I had a tough opponent, so I was really happy to get through," said the Dane. "I was feeling confident on the court and comfortable.
"I'm really happy about the way things are going and I've been practising hard, so I'm really pleased about the way I'm playing."
Victoria Azarenka, the seventh seed, had no trouble seeing off Stephanie Cohen-Aloro 6-2 6-0, and ninth seed Vera Zvonareva beat Kristina Kucova by the same score.
Belgium's Yanina Wickmayer continued her recent run of excellent form by knocking out 12th seed Flavia Pennetta 7-6 (7-2) 6-1.
Wickmayer, 20, won the Auckland Classic title earlier this month in her first tournament since a court overturned a one-year ban for breaking doping regulations.