Alexander Zverev has beaten Rafael Nadal in their opening round-robin match of the ATP Finals.
The loss dents Nadal's chances of ending the year as the number one ranked tennis player in the world.
He entered the season-finale in London with an abdominal injury.
Tuesday's match sees Roger Federer, who also lost his opening encounter, take on Italy's Matteo Berrettini.
Play gets underway at 6:00 pm UAE time.


Jordan qualifies for the FIFA Arab Cup final
Sharjah Warriorz make it two in two with 11-run win over Gulf Giants
Bournemouth rescue draw with Man United in eight-goal thriller
Morocco beat UAE to reach FIFA Arab Cup final
Mid East Falcons win inaugural United Series Championship in Dubai