Defending champion Iga Swiatek has been knocked out of the WTA Finals in Saudi Arabia after group rival Barbora Krejcikova beat Coco Gauff to secure her place in the semi-finals .

Barbora Krejcikova grabbed the last semifinal spot at the WTA Finals with a 7-5, 6-4 win over Coco Gauff, a result that eliminated second-ranked Iga Swiatek from the season-ending tournament.

Defending WTA Finals champion Iga Swiatek was eliminated from the season-ending championship on Thursday after Barbora Krejcikova's 7-5 6-4 win over Coco Gauff meant the Polish world number two failed to advance to the last four.