Gauff's serve changes are still embedding into her tennis. But she has other ways to win when the double faults start.

It’s not often that the world No. 2 goes two months without winning a match, but that’s the reality Coco Gauff was facing late Tuesday night in Montreal, on the cusp of a third consecutive loss, this time in her opening duel at the Canadian Open.

After being pushed all the way by compatriot Danielle Collins in her first match in Montreal, Gauff was forced to dig deep yet again to seal a 4-6 7-5 6-2 win over Kudermetova