LONDON, Nov 16 — Rafa Nadal's began his quest to fill the one blank on his glittering CV in impressive fashion with a crushing 6-3 6-4 defeat of debutant Andrey Rublev at the ATP Finals on Sunday.

The Spanish 20-time Grand Slam champion has never won the season-ender, reaching only two finals, but looked in menacing form against Russian youngster Rublev.

World number two Nadal broke serve in the sixth game of the first set on his way to the opening set.

Rublev, whose five titles this year was more than any other player on the ATP Tour, became visibly frustrated as he could make no impression on the rock-solid Spaniard having dropped serve at the start of the second set.

Nadal was clinical on serve and wrapped up victory in his opening round-robin match in the London Group in 77 minutes. In the earlier match US Open champion Dominic Thiem beat last year's champion Stefanos Tsitsipas. — Reuters