Defending champion Roger Federer began his quest for a record seventh Australian Open title with a 6-3, 6-4, 6-4 win over Denis Istomin.

Switzerland's Roger Federer celebrates after defeating Uzbekistan's Denis Istomin during their first round match at the Australian Open tennis championships in Melbourne, Australia, Monday, Jan. 14, 2019.(Photo: AP)

Playing before a capacity crowd of more than 15,000 at Rod Laver Arena, Federer broke Istomin's serve at 2-2 in the third set on the way to his seventh win in a row without a loss against the Uzbekistan player.

Federer's seventh Australian Open title would be the most by any player. Novak Djokovic, who plays his first-round match on Tuesday, and Roy Emerson, also have six wins each at the Australian Open, although Emerson's wins were before the start of the Open era in 1968.

A win in Melbourne would also be Federer's 100th tour-level title, the second man after Jimmy Connors to win 100 titles. Connors had 109.