Roger Federer still cannot believe that he has the opportunity to become the world number one this week after deciding to play the Rotterdam Open and admits it will mean a lot to his family and coaching team.

The Swiss ace is just 155-points behind Rafael Nadal in the ATP rankings and a run to the semi-finals in Netherlands will see him start the week beginning 19 February as the new world number one.

Federer has a relatively easy run to the last four with a potential quarter-final clash with Stan Wawrinka — the only obstacle between him and the top spot in men's singles. And if he reaches that spot, the 36-year-old will become the oldest player to achieve the number one ranking beating Andre Agassi's record — the American was 33 when he became the top ranked men's singles player in 2003.

However, despite the relatively easy run, the Swiss tennis legend is not taking anything for granted and is aware that it will be a hard week. Federer's return to the summit in the ATP rankings will be a culmination of his incredible comeback since suffering a knee injury and missing the second half of the 2016 campaign.

Federer has won eight titles in just over 12 months since making his comeback last January, which includes three Grand Slams — two Australian Open titles and a record eighth Wimbledon Championship.

"It would be absolutely incredible," Federer said ahead of his first match at the Rotterdam Open, as quoted by the Express.

"I can't believe I'm this close, but No 1 has never been simple, never been easy to get there so I know it's going to be a lot of hard work for me this week.

"Mentally, to cope with everything and also not thinking too far ahead because I'm not there yet. As long as you're not world No 1, you're not. It's that simple," he added.

"I think it would also mean a lot to my family, my team and my fans; everybody that has been so supportive along the way.

"My comeback since '16 has been so incredible that we're already happy as is but I thought I'd give it a go and see if I can get No 1 this week," the 20-time men's singles Grand Slam winner explained.

Roger Federer
Roger Federer is favourite to take over the world number one ranking from Rafael Nadal Getty