Federer is enjoying the tug of war with Nadal over the No. 1 ranking

Roger Federer is enjoying his tussle with Rafael Nadal for the No. 1 ranking, with the two having exchanged it five times between them this season.

Federer grabbed the top spot and became the oldest No. 1 in rankings history when he won the title at an impromptu appearance at Rotterdam. The No. 1 ranking has been in play at almost every event he and Rafa have played since.

It is in contrast to the relative stability at the top in recent years, though Novak Djokovic's record points total and Andy Murray's ascent to the top spot in 2016 did draw attention to the rankings.

"There was not a lot of talk about No. 1," Federer said. "Now it's been exciting.

"It's great for the fans that it's been going back and forth. It's quite fun at the moment."

Strokes of Genius trailer - A documentary on Federer vs. Nadal at Wimbledon in 2008:

Getting to compete for the No. 1 ranking also adds to his enjoyment of matches, noted Federer, who had to win his Stuttgart semifinal against Nick Kyrgios to move back in front of Nadal. He did just that, coming from a mini-break down in a third-set tiebreaker to win.

"These kind of matches don't come around so often. When you play for it and it's not in a Grand Slam final [but] at a 250 or 500, it feels different," he said. "I'm very happy...getting there especially with 7-6 [win] in the third-set tiebreaker."

And with Federer and Nadal just 150 points apart in the rankings, the tug of war could be set to keep going. Having now grabbed back No. 1, Federer will have to defend his title in Halle this week to keep it. Otherwise, Nadal will be back in the top spot next week.

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