Roger Federer can write a new chapter in his phenomenal return from injury by replacing Rafael Nadal as world number one this month after accepting a wildcard into the Rotterdam Open.
Federer will be number one if he reaches Rotterdam semis
If Federer, who claimed his 20th grand slam at the Australian Open last month, makes the semi-finals in the Netherlands he will move to the top of the rankings for the first time since November 2012.
The veteran Swiss sat out the majority of 2016 due to back and knee injuries and dropped as low as 17th in the rankings, but he has won three of the last five majors and is now closing in on a return to the summit.
Speaking about his participation in the Rotterdam Open, which begins next Monday, Federer said: "The tournament is special for me. I remember playing for the first time in 1999 as it was one of the first events where I got the chance to play at the highest level. It feels good to join in the celebrations of the 45th edition."
Tournament director Richard Krajicek added: "After his fantastic result at the Australian Open, it is tremendous news that he will be joining us in Rotterdam. It is a crown to the celebration of the history of our tournament.
"The last 12 months have shown his tremendous drive. It makes perfect sense that he wants to capitalise on his current form."
Federer would be oldest player to top men's rankings
Federer won the Rotterdam Open in 2005 and 2012 and will eclipse Andre Agassi as the oldest male number one if he reaches the final four this time around.
Nadal is not scheduled to play again until the Mexican Open in Acapulco in the last week of February.