In-form Gauff sweeps past Kenin to fire Australian Open warning
The world number three, who is unbeaten this year after leading the US to win the United Cup, eased past the 2020 Melbourne Park winner 6-3, 6-3 in 80 minutes.
"I knew it was going to be difficult, but you know, I'm happy with how I played," said Gauff, the 2023 US Open champion who admitted to being troubled when serving by the fierce Melbourne sunshine.
"I maybe could have had a better second serve, but on that side, I was struggling to see the ball, so I was just happy I was able to manage through that today."
The gutsy Kenin, ranked 74th, did not go down without a fight but could only convert one of her six break-point opportunities and had no answer to Gauff's 28 winners.
Gauff will face 173rd ranked Briton Jodie Burrage in round two.
The American has been on a scintillating run of form that has made her a major threat to double defending champion Aryna Sabalenka at Melbourne Park.
The pair are drawn to meet in the semi-finals which would be a repeat of their last-four encounter 12 months ago, when the Belarusian won in straight sets.
The 20-year-old Gauff finished 2024 with a flourish by winning the China Open and the season-ending WTA Tour Finals.
She took that form to Australia, winning all her singles matches at the United Cup including beating world number two Iga Swiatek in straight sets.
Gauff changed coaches in the autumn after her US Open defence fell flat, parting with Brad Gilbert and bringing in the little-known Matt Daly.