LONDON (Reuters) - They know a thing or two about time in Switzerland -- their cuckoo clocks, expensive wristwatches and unerring railway timetables are proof of that.

Tennis - ATP 500 - Rotterdam Open - Quarterfinal - Ahoy, Rotterdam, Netherlands - February 16, 2018 Roger Federer of Switzerland and Tournament Director Richard Krajicek acknowledge the audience. REUTERS/Michael Kooren

Yet it is the Alpine nation’s favorite son, Roger Federer, who has apparently mastered the art of reversing it.

The Peter Pan of men’s tennis took his time machine to Rotterdam this week and on Friday posted a 4-6 6-1 6-1 victory over Dutchman Robin Haase to reach the semi-finals of the ABN AMRO tournament.

In doing so he is guaranteed a return to number one in the ATP world rankings for the first time since November 2012.

The 36-year-old father of two sets of twins becomes the oldest man ever to top the standings, replacing American Andre Agassi who was 33 when he last held the top spot in 2003.

Not only that but the gap of five years and 106 days between separate stints at the summit is the longest in ATP history.

He also sets a new record for the longest time between debuting as world number one (in 2004) and his latest stint -- a record previously held by Rafael Nadal, the man Federer has knocked off the top of the pile.

Since Federer lost the top spot in 2012, when many predicted his best days were done, Novak Djokovic, Nadal and Andy Murray have all had lengthy periods on the throne but whereas the clock ticks ever louder for that battle-ravaged trio, Federer appears to have found a new dimension.

GOLDEN CHAPTERS

He is producing one of the best late-career runs by any sportsman. He claimed a record-extending 20th grand slam title by winning the Australian Open for a second successive year last month, becoming the oldest player to triumph in Melbourne since Ken Rosewall in 1972.

Incredibly, since turning 35 -- an age still considered beyond the sell-by-date in the high-octane world of top-level tennis -- Federer has won three of the last five grand slam titles on offer playing arguably the best tennis of his career.

Those craving eternal youth really should have a look at this man’s DNA.

Yet Federer, for all the unique magic that other players can only dream about, offers a far more pragmatic explanation for his ability to make a mockery of the aging process.

When he was sidelined by a knee injury in 2016, forcing him to skip the French Open and snap a streak of 65 consecutive grand slam appearances, Federer took a career time-out.

Though he played at Wimbledon that year, soldiering on to the semi-finals, he then shut down his season and came up with a formula designed to protect his knee and back and give him the chance to add several golden chapters to his career.

Quality not quantity was the essence of it and in 2017 he returned to play 12 tournaments, winning seven of them, including the Australian Open, a record eighth Wimbledon and Masters 1000 titles at Indian Wells, Miami and Shanghai.

“My philosophy is I play when I’m ready. What I did last year and what Rafael (Nadal) is doing also is maybe a bit of a lighter schedule,” he said this week in the Dutch port city.

“It shows to others by working or practicing a bit more... you become a different or better player.

“I hope I take that fear away a little bit, that sometimes it’s OK to take time.”

Easy to say for an athlete for whom the clock appears to be slowing down, rather than speeding up as it does for mere mortals as the years pass, but fellow 30 something Nadal, Murray and Djokovic will take heart from his words of wisdom.