Aryna Sabalenka says biomechanics coach Gavin MacMillan helped her find a way out of "a desperate situation," and hopes the biomechanics expert can do the same with Coco Gauff.

Coco Gauff hired Gavin MacMillan, a biomechanics coach credited with rebuilding No. 1-ranked Aryna Sabalenka’s serving motion in 2022.

Coco Gauff, the most popular American tennis player, hadn’t been able to book a practice court. So, she and her newly hired coach, biomechanics expert Gavin MacMillan, braved the mist for close to an hour as they worked on trying to fix her serve.