Angry Andry Rublev was sensationally defaulted on Friday from a Dubai Quarter final in a controversy over alleged swearing at a linesperson, with stunned opponent Alexander Bublik handed a 6-7(4), 7-6 (5), 6-5 decision.

Rublev, fourth in the world and the second-seeded defending champion was called out to the chair umpireĀ  by a linesman who claimed to be a Russian speaker.

The linesman said Rublev swore in his native language to a colleague on court at the Aviation Club after a call which gave Bublik a 6-5 lead in a tight final set.

Rublev immediately protested his innocence, telling the tournament supervisor  and the chair he only spoke in English before being defaulted in a scene which shocked fans.