Tsonga next plays Federer, who is No. 6 at this Australian Open, his lowest seeding in more than a decade, after a year in which he didn’t reach a Grand Slam final for the first time since 2002.
Last year, Federer beat Tsonga in the quarterfinals here.
“For me it’s going to be the possibility to have revenge,” Tsonga said.
Murray, playing only his second tournament since minor back surgery in September, only dropped one service game in a 2-hour, 15-minute match and next faces Stefane Robert, a lucky loser from qualifying, who is into the fourth round for the first time after beating Martin Klizan.
“It’s been a good start,” Murray said. “It was very tricky the first couple of matches with the heat, but today was beautiful to play in.”
Sharapova will next play Dominika Cibulkova, who beat No. 16 Carla Suarez Navarro 6-1, 6-0. Former No. 1-ranked Jelena Jankovic had a 6-4,7-5 win over Kurumi Nara, her third consecutive victory over a Japanese player.
Fifth-seeded Agnieszka Radwanska had a 5-7, 6-2, 6-2 over No. 29 Anastasia Pavlyuchenkova and will next play Garbine Muguruza of Spain, who ousted former No. 1-ranked Caroline Wozniacki 4-6, 7-5, 6-3.
Stephens, who had an upset win over Serena Williams in the quarterfinals here last year, reached the fourth round at a fifth consecutive major with a 7-5, 6-4 win over Elina Svitolina.
Williams will play her fourth-round match Sunday against 2008 French Open champion Ana Ivanovic. Three-time defending champion Novak Djokovic plays Fabio Fognini in an afternoon match on Rod Laver Arena.