Roger Federer knows he has his work cut out for him as he prepares to make his bid for the ATP’s No.1 ranking this week at the ABN Amro in Rotterdam.

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“It’s going to be a lot of hard work for me,” said Federer. “Mentally, to cope with everything.”

Federer will face Ruben Bemelmans on Wednesday in Rotterdam, and if he wins he’ll face Germany’s Philipp Kohlschreiber next. The Swiss needs to reach the semifinals in order to claim the No.1 slot for a 303rd week.

If he does so he will become the oldest No.1 in ATP history and he will also break the record for longest stints between stays at No.1--14 years.

“It would be absolutely incredible,” Federer said. “I can’t believe I’m this close.”

Federer could face Stan Wawrinka in the quarterfinals.

“I think it would mean a lot to my team,” Federer said. “My family, my fans, everybody who 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 could get to World No.1 this week.”