Federer can become world No 1 for the first time since 2013 if he reaches the semi-finals of the Rotterdam Open this week.
The Swiss star is 155 ranking points behind current world No 1 Rafael Nadal, who is not expected to return to action until the end of the month.
At 36, Federer would become the oldest men’s world No 1 in history, surpassing Andre Agassi.
And it would cap a stunning 13 months which has seen him win three Grand Slams.
Federer gets his campaign underway this afternoon (6.30pm) against Belgian Ruben Bemelmans.
And speaking ahead of the match, Federer opened up on what becoming world No 1 would mean for him.
Federer said: ”I think it will be unbelievable for my team, you know.
“Maybe more so than for myself personally, but a lot of guys have put in so much work over the last decade and so forth – for all my coaches for that matter, you know, that I was able to stay motivated and keep going for as long as I have and then to reward everybody along the way with maybe a world number one would be very special, regardless of whether I make it or not.
“It just would look nice to be world number one again.
“But I’m not there yet, it’s not going to be easy, I know that, world number one has never been easy, so I’m going to try and see what happens this week.”