The Latest on Wednesday from the Australian Open (all times local):
Kei Nishikori advanced to the third round in a far more straightforward manner than his five-set opener earlier this week.
The fifth-seeded Nishikori defeated Frenchman Jeremy Chardy 6-3, 6-4, 6-3 in just over two hours to reach the third round for the seventh consecutive year.
On Monday, he needed 3 1-2 hours before beating Andrey Kuznetsov in the first round.
"(I) was definitely playing much better than first round today," he said Wednesday. "There were many ups and downs, still too many break points for me. Great to finish in three sets."
Nishikori has reached the quarterfinals three times at Melbourne Park, but has never advanced beyond that stage. He could play top-seeded Andy Murray in the quarterfinals this year.
Venus Williams, a first-round loser in 2016 at Melbourne Park, is one of the first players into the third round this year after beating Stefanie Voegele 6-3, 6-2 to begin play at Rod Laver Arena on Wednesday.
Williams maintained a perfect 3-0 record against the Swiss player, having beaten her on clay at Madrid, grass at Wimbledon and now hard courts in the year's first Grand Slam tournament.
Voegele wasn't helped by four double-faults in the opening set. In the second, Williams broke Voegele's service with a blistering forehand to the open court to take a 3-1 lead, then broke her serve again in the final game.
Williams lost to eventual semifinalist Johanna Konta in the opening round last year.
The older sister of Serena Williams, Venus Williams has never won the Australian Open. She lost the 2003 final to Serena. Venus' best recent finish here was a quarterfinal appearance in 2015.
Defending champion Angelique Kerber and top-seeded Andy Murray play their second-round matches on Wednesday in much more pleasant temperatures at Melbourne Park.
A cool change hit the city overnight, dropping temperatures from 38 Celsius (100 Fahrenheit) on Tuesday afternoon to about 20 Celsius (68 Fahrenheit) when play began Wednesday.
Venus Williams was first up on Rod Laver Arena, playing Stefanie Voegele of Switzerland. Kerber was to follow against fellow German Carina Witthoeft, followed by Roger Federer against American qualifier Noah Rubin.
Murray was scheduled to play the last match on Wednesday night at Rod Laver.
Venus and Serena Williams were scheduled to play their opening doubles match on Wednesday afternoon.