Novak, Serena win in straight sets, but heat takes toll as Dodig becomes 10th player to retire.
The bet is placed before legitimate betting agencies are able to close off wagering.
Mannarino looked to be struggling in temperatures in excess of 37 degree during last two sets.
Novak Djokovic next plays Russian 30th seed Dmitry Tursunov.
Serena Williams won almost 90 percent of her first serve points.
Murray swept into the second round with a 6-1, 6-1, 6-3 rout of Japan’s Go Soeda.
The unseeded Indian showed a lot of fighting spirit before going down 4-6 4-6 6-7 (2) to World No. 27.
With temperatures soaring, Open heats up on Day Two with enthralling five-setters and excruciating pull-outs.
Sharapova was made to work hard for her passage into the second round.
Nadal will play Australian wildcard Thanasi Kokkinakis in the second round.
Del Potro steadied in the second set and cruised to victory in just over three hours.
Murray will next play the winner of Vincent Millot or another qualifier in Wayne Odesnik.
The 29-year-old sat with a bag of ice on his head and had plenty more stuffed into a towel around his neck.
Federer next faces the winner of Czech Radek Stepanek and Slovakian Blaz Kavcic.
Azarenka made a stuttering start to her bid for a third straight Australian Open title.
Boris Becker joined Novak Djokovic as his new head coach in December.
With Boris Becker in his box, defending champ Djokovic shakes off rust with straight-sets win in 1st round.
Unlike Ivan Lendl, Becker was animated as he sat with the rest of the Djokovic team.
Petra Kvitova fell victim to Thai world number 88 Luksika Kumkhum on Margaret Court Arena.
Wood said there has never been anybody who has died from dehydration on a tennis court.
Thai world number 88 Luksika Kumkhum sprang the biggest upset of the Australian Open's first day.
The serve-and-volley specialist was curious to see what changes Djokovic and Federer bring to their game.
Djokovic admitted that tennis changed radically since Becker won six grand slam titles.
Nadal has thrived on slower surfaces, winning eight of his 13 grand slam titles.
Del Potro served with venom and unleashed powerful forehands and backhands.