They met last year in the Wimbledon final (won by Alcaraz) and Olympic final (won by Djokovic).The top seed is Jannik Sinner, who won the Australian Open and U.S. Open last year. He can break his tie with Nicola Pietrangeli for the most Grand Slam singles titles for an Italian.

The Australian Open kicks off each year's tennis Grand Slam tournament circuit. Who has taken home titles? Check out this all-time champions list.

The reigning men's champion Jannik Sinner got his defence underway with a win against Nicolas Jarry, while two-time women's champ Aryna Sabalenka made light work of former US Open