Roger Federer admitted that it was something of a dream come true to have secured a return to the top of the world rankings at the age of 36.
The 20-time Grand Slam champion ensured that he will be at the summit by beating Robin Haase 4-6 6-1 6-1 to reach the semi-finals of the Rotterdam Open, with the Swiss maestro being confirmed as top dog on Monday, when he will move above great rival Rafael Nadal.
The goal was to be world number one for a week, that's plenty for me.Roger Federer
And Federer, who was last at number one in 2012, was a happy man, especially as he had to do the business on court to gain his reward.
He told reporters: "I think it was great that I had to play for it this week. I didn't just get it by Rafa losing somewhere or dropping points or me sitting on the sidelines, like in 2012 when I was on holiday and got the ranking two weeks after Wimbledon.
"This way, to play a match where you know that you are going to be world number one if you win it, in front of a crowd, is a great feeling."
Meanwhile, Federer, a two-time champion in Rotterdam, says he has achieved his main goal for the week, but now wants to tray and go all the way and complete a hat-trick of wins in the Dutch port city.
Ahead of a semi-final match-up with Andreas Seppi he added: "The goal was to be world number one for a week, that's plenty for me. If it's more, great, I'll take it. If I play well, good things will happen.
"It's the ultimate achievement in our sport to get the number one ranking, it just doesn't come easy. This one means the most at 36 years of age, almost 37."
Federer, who holds a 13-1 winning record over Seppi, is 1/1 to defeat the Italian again on Saturday and is 1/1 to do so in two straight sets, with the Swiss 1/3 to claim the title in Rotterdam.
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