World number 36 Kyrgios, who was broken in the third set, threw his racket to the floor before kicking a water bottle and flinging a chair towards the centre of the court.
Ruud was leading 6-3 6-7(5) 2-1 when Kyrgios was disqualified.
Sabalenka downs world number one Barty to claim Madrid crown
(Reporting by Hardik Vyas in Bengaluru, editing by Pritha Sarkar)
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