Antonsen had to fend off a match point and was in great difficulties when he managed to defeat the Canadian Brian Yang, who is ranked no. 32 in the world.
Antonsen won 21-17, 19-21, 23-21 over the Canadian in the Super 750 tournament in France.
Later on Thursday, Axelsen also lived up to his favorite status when he met the Taiwanese Chou Tien Chen. Axelsen, who is currently ranked 26th in the world, won in two sets, 21-11, 23-21.
The first set was convincing from Axelsen, who beamed with energy and gave evidence of his entire repertoire. Axelsen then got into big trouble in the second set, where the Taiwanese squandered a set point.
Instead, Axelsen took advantage of his second match point to win the match.
Axelsen's and Antonsen's wins completed an astonishing Danish day at the prestigious tournament as the Danish mixed doubles pair with Mathias Christiansen and Alexandra Boje defeated the world no. 1 pair of Jiang Zhenbang and Wei Yaxin from China.