"I'm happy with the serve. It was the key today," Rybakina said.

Defending champion Aryna Sabalenka fell to a 6-1 6-4 defeat by Elena Rybakina in the quarter-finals of the Cincinnati Open.

Rybakina fired 11 aces throughout the match, earning an impressive 81% of points on her first serve, while saving all five break points she faced as she secured her fifth win over Belarusian Sabalenk...