Even with the roof closed, Venus Williams sees no ceiling on Coco Gauff's future.

In a battle of the ages, the 15-year-old Gauff topped the 39-year-old Williams 7-6(5), 6-3 earning her first Australian Open victory.

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It was Gauff's second Grand Slam victory over one of her tennis idols following her straight-sets victory over the five-time Wimbledon winner in the opening round of The Championships last summer.

The oldest woman in the field had high praise for the youngest.

"(She) just played very focused and put a lot of balls in the court," Williams said. "That's what you have to do. She'll play well the rest of the event.

"I mean, she clearly wants it, works very hard, is extremely mature for her age. I think the sky's the limit for her."

Photo credit: Mark Peterson/Corleve