Australian Open champion Elena Rybakina fell to a shock 7-6 (10/8), 6-4 defeat by Anastasia Potapova on Monday in the Madrid Open fourth round. Earlier world number one Aryna Sabalenka overcame Naomi Osaka 6-7 (1/7), 6-3, 6-2 in a gripping battle to reach the quarter-finals. Third seed Coco Gauff was eliminated in a three-set battle with Linda Noskova decided on a final set tie-break in an e... [3597 chars]