Roger Federer has opened up about his former rivalry with fellow Big Three member Rafael Nadal.

Former world No. 1's Federer and Nadal fostered a historic rivalry over their decades-long careers. The Swiss and the Spaniard, who have 20 and 14 Grand Slam titles to their names respectively, faced each other 40 times with Nadal leading 24-16 overall.

They held the top two positions in the ATP singles rankings from July 2005 to August 2009, and their head-to-head at the 2008 Wimbledon final is considered by many as the greatest match in tennis history.

Therefore, it is unsurprising that over this time the pair formed a strong bond.

Whilst interacting with fans at a Uniqlo event in New York last month, Federer recalled how his bond with the 37-year-old developed over the many years in which they faced each other, saying:

"I'm five years older than Rafa. So when I came on tour, I saw young, junior Rafa come through and he was extremely good, very young, incredibly respectful and also very shy. So he had unbelievable respect for me, not that he doesn’t have now anymore, I guess it's different because we’re friendly. So earlier... With everything that I wanted to do on the tour and my ideas he was like, ‘You’re right!

"Then I saw Rafa grow into his personality, he got more confident and then we started playing each other every other weekend and obviously got the rivalry very tennis but always got along well… Not only the two of us but also our teams - My parents, his parents; my coaches, his coaches; my sister, his sister," he said.

The 41-year-old went on to talk about how their lives have moved on from tennis, but that both he and Nadal respect and sometimes miss the great sporting rivalry they once had, even though at at times it meant they 'couldn't stand each other':

"I think as we got older, we knew the time is ticking and we’re about to not see each other so much anymore. I started a family… that changes someone completely anyway. And we started to talk about totally different things in life… more about injuries and kids… he’s also a father now. So the conversations changed.

"We also started respecting the rivalry we used to have and we almost miss it, playing each other every other weekend. Back in the day we couldn’t stand each other probably for that but he is a great man and I wish he can come back one more time," he said.