Britain’s Alfie Hewett began his reign as world number one with a win to set up an Australian Open quarter-final against doubles partner Gordon Reid in the men’s wheelchair event.
The top seed delivered a performance worthy of his new title with a 6-1 6-0 victory over Japan’s Daisuke Arai.
Reid beat Tom Egberink 6-1 3-6 6-4.
Reid, the 2016 champion, defeated Egberink in a rain-broken third set at Melbourne Park.
However, 17-year-old compatriot Ben Bartram was beaten on his senior Grand Slam debutlosing 6-0 3-6 6-3 against the Japanese Takashi Sanada.
Hewett is in contention for a first singles title at the Australian Open, having lost to Kunieda in last year’s final.
The US Open champion launched his title bid with a bang, hitting 27 winners in an hour and 22 minutes.
Hewett and Reid will begin their bid for a fourth straight doubles title in Melbourne against Joachim Gerard and Takuto Niki on Wednesday.