The latest from the Australian Open (all times local):
Sixth-seeded Thomas Berdych advanced to the second round with a 7-5, 6-1, 6-2 win over Yuki Bhambri in a straight-forward opener to his 50th consecutive major tournament. Bhambri was playing his first tour-level match since the last Australian Open.
The 30-year-old Berdych served 13 aces and had only one double-fault, and advanced beyond the first round for the 11th straight year at Melbourne Park. He reached the semifinals last year before losing to four-time finalist Andy Murray, his best run at the season's first Grand Slam tournament.
Sloane Stephens lost 10 straight games before losing her first-round match at the Australian Open to Chinese qualifier Wang Qiang 6-3, 6-3.
The No. 24-seeded Stephens was up 3-1 in the first set and then lost 10 games in a row to the Chinese player, who is ranked 102nd.
Stephens won her second career title in Auckland earlier this month but then withdrew from the Hobart International due to a viral illness.
Stephens reached the semifinals at the Australian Open in 2013.
Defending champion Serena Williams has won her first-round match, beating Camila Giorgi of Italy 6-4, 7-5 on Rod Laver Arena.
Williams, who just missed a calendar-year Grand Slam in 2015 when she lost in the U.S. Open semifinals, was helped by 12 double-faults by the Italian player, including on break point in the 11th game of the second set to give Williams a 6-5 lead.
The 21-time major champion held her service at love in the next game, including two aces and a service winner, to close out the match in 1 hour, 45 minutes.
Williams appeared to show no soreness from recent inflammation in her left knee.
"It wasn't quick, so that actually worked to my advantage as well," Williams said. "I think I was able to stay in it and stay calm today and I think that's what matters most."
Kei Nishikori has become the first of the seeded men's players to advance to the second round of the Australian Open.
The seventh-seeded Nishikori, who reached the quarterfinals last year, beat Philipp Kohlschreiber 6-4, 6-3, 6-3 without facing a break point Monday.
Nishikori struggled with a series of injuries last year, but said he was feeling sharp after his first match in Melbourne.
"It's great to finish in three sets, especially against Philipp. He's always tough to play," Nishikori said. "The body is feeling pretty good. I had a good preparation."
Kohlschreiber, ranked No. 34, was the highest ranked of the men's players who were unseeded at the tournament.
ATP chairman Chris Kermode and the Tennis Integrity Unit have rejected news reports that match-fixing has gone unchecked in the sport.
In reports published on the morning the Australian Open began, the BBC and BuzzFeed News said secret files exposed evidence of widespread suspected match-fixing at the top level of world tennis. The report said that in the last decade 16 players — all at some stage ranked in the top 50 — have been repeatedly flagged to the integrity unit.
The reports say the players — it doesn't identify them or say whether they were involved in singles or doubles — were allowed to continue competing.
At a news conference at Melbourne Park on Monday, Kermode said officials "absolutely reject any suggestion that evidence of match-fixing has been suppressed for any reason, or isn't being investigated."
Nigel Willerton, head of the Tennis Integrity Unit which was formed in 2008 as a joint initiative of the International Tennis Federation, the ATP, the WTA and the Grand Slam Board, says "it would be unprofessional for me to comment on if any players here are being monitored."
Two-time Wimbledon champion Petra Kvitova has the distinction of winning the first completed match at the 2016 Australian Open, avenging a loss to Luksika Kumkhum from two years ago.
Kvitova beat the Thai qualifier 6-3, 6-1. In 2014, Kumkhum beat Kvitova in three sets to send the-then sixth-ranked player out of the tournament.
Serving to stay in the match Monday, Kumkhum saved two match points before double-faulting in the breezy conditions on Rod Laver Arena to hand Kvitova the match in 70 minutes.
Kvitova won her Wimbledon titles in 2011 and 2014. Her best performance at the Australian Open is a semifinal berth in 2012.
Under sunny skies and a temperature of 30 Celsius (86 Fahrenheit), two-time Wimbledon champion Petra Kvitova has begun play in her first-round match against Luksika Kumkhum of Thailand, the first match on the center court at the Australian Open.
Over on Hisense Arena, 2014 U.S. Open finalist Kei Nishikori of Japan is playing Philipp Kohlschreiber of Germany.
Later matches on Rod Laver Arena involve the defending champions Serena Williams and Novak Djokovic. Williams, who just missed a calendar year Grand Slam last year by losing in the semifinals at the U.S. Open, plays Camila Giorgi of Italy, followed by Djokovic's match against Chung Hyeon of South Korea.
An International Tennis Federation spokesman at the Australian Open says the Tennis Integrity Unit plans to issue a statement on Monday in reaction to reports over match-fixing in the sport.
The BBC and BuzzFeed News says secret files exposed evidence of widespread suspected match-fixing at the top level of world tennis. The report said that in the last decade, 16 players who have been ranked in the top 50 have been repeatedly flagged to the integrity unit.
The reports say the players — it doesn't identify the players or say whether they were involved in singles or doubles — were allowed to continue competing.
The Tennis Integrity Unit was formed in 2008 as a joint initiative of the ITF, the ATP, the WTA and the Grand Slam Board.