Four-time winner Roger Federer progressed to the Australian Open third round by holding off the challenge of American prospect Noah Rubin.
The 35-year-old Swiss, who is seeded 17th after missing the second half of the 2016 season with a knee injury, saved two set points in the third to win 7-5 6-3 7-6 (7-3).
Federer will play 2010 Wimbledon finalist Tomas Berdych next.
Elsewhere, fifth seed Kei Nishikori overcame France's Jeremy Chardy.
The 27-year-old from Japan, who has reached the quarter-finals in the past two years, came through 6-3 6-4 6-3 in two hours six minutes to set up a meeting with Slovak qualifier Lukas Lacko.