Elina Svitolina produced a merciless performance as the top seed blitzed Kristina Mladenovic to advance to the Chicago Women's Open semi-finals.

Mladenovic was no match for Svitolina, who steamrolled the seventh seed in a brutal 6-1 6-0 victory at the WTA 250 tournament on Thursday.

Ukrainian star Svitolina reeled off the last 11 games to set up a semi-final clash with Rebecca Peterson.

Peterson moved through 7-6 (7-4) 2-6 4-1 after Tereza Martincova retired hurt.

French ninth seed Alize Cornet rallied past fifth seed Marketa Vondrousova 2-6 6-4 6-3, while eighth seed Marta Kostyuk won the first set 7-6 (7-4) but trailed Varvara Gracheva 5-3 in the second before the match was suspended due to darkness.

At Tennis in the Land, top seed Daria Kasatkina was upstaged by Magda Linette 6-1 6-2 in the quarter-finals.

Second seed Anett Kontaveit survived 6-3 5-7 7-2 against Katerina Siniakova in Cleveland, while fellow seed Sara Sorribes Tormo also won through to set up a semi-final clash.