The Italian first claimed the number one ranking in June last year and held it for 65 weeks until he lost the US Open title-match to Alcaraz in September.

The six-time Grand Slam champion has failed to win the Paris Masters in five attempts and now faces losing his place atop the rankings should rival Jannik Sinner win the tournament.

Novak Djokovic rallied to defeat Andrey Rublev 5-7, 7-6 (7/3), 7-5 in a gripping Paris Masters semi-final on Saturday, earning a shot at a record-extending seventh title in the final against Grigor Dimitrov.

Marin Cilic dumps a struggling Novak Djokovic out of the Paris Masters quarter-finals to pave the way for Andy Murray to become the new world number one.