Roger Federer has signed up to play at the ABN AMRO World Tennis Tournament in Rotterdam next week where he could be crowned world No 1.
Federer successfully retained his Australian Open crown with a five-set victory over Marin Cilic last month to find himself just 155 points behind top-ranked Rafael Nadal.
But with the Spaniard not scheduled to play until the end of February in Acapulco the door has opened for the 36-year-old to become the oldest-ever world No 1 with a run to the semi-finals enough to see him overtake his long-time rival at the 500 event.
