Australian Alex de Minaur emerged from a marathon day of tennis to claim his first ATP title, beating Andreas Seppi 7-5 7-6 (7-5) in the Sydney International final.

Forced to win through his semi-final on Saturday afternoon against Gilles Simon after rain washed out play on Friday night, de Minaur returned for the gutsy straight-sets win over Seppi five hours later.

The victory made him the youngest winner of the tournament since Lleyton Hewitt also did it as a 19-year-old in 2001.