Roger Federer had nothing but positive things to say about Rafael Nadal, reflecting on how their relationship has developed over the years since the first time they met.

The two tennis heavyweights have locked horns multiple times over the past decade or so with each clash always garnering the biggest of audiences.

Though they often competed for the same trophies, both players still had their fair share of wins in terms of medals or even over one another.

Nadal is the younger of the pair, but has arguably had tougher spells to get through as he has had to deal with recurring injuries throughout his career.

Federer, though, maintains a great deal of respect for his rival and he insists it's a friendly rivalry that has never gotten ugly.

According to Tennis World USA, Roger said: "First time I remember him I guess was when I saw him play - I don't know. I don't quite remember what tournament it was, but obviously the first time I played against him in Miami.

"I knew he was very good already, and then I lost also the first time we played against each other. I think I must have been world no. 1, too.

"So a teenager who can beat any world No. 1 obviously I knew is going to become a future champion really. Even though it's just one match, there's still so much work he has to do, which clearly he did.

"So I think he's always been quite respectful. Obviously, he's younger than me, maybe looked up to me at the very beginning. So I think he was always very respectful.

"I've always been the same to any opponent really. So I think, from the start, it was just mutual respect. Didn't speak much at the very beginning, was shy.

"As time went by, we had to spend more time together, and we played more against each other. We started to, I don't want to say hang out more together, but we saw each other more and started to speak more together.

"It was always friendly and it was always very nice. So from this standpoint, we never really had any issues together.

"Depending on the subject. We talk about many things. But tennis probably being one of them at times, yeah."

Rafael is currently ranked in first place while Federer is in second, showing not only how close they are on the court, but also in profile and ability.

Arguably their biggest challenger is Novak Djokovic, who is close behind in third place and keen on climbing back up the ranks to establish himself as the best in the world.

It's no surprise, however, to learn that Nadal and Federer always kept a respectful and positive relationship as it reflected on the court as well.

No matter how heated matters got during their famous clashes, neither player lost their heads with the other or anything of that sort.

With Djokovic on their tails, though, the talented duo will have to step it up to keep him at arms length or risk losing some shine to their respective legacies.

What made Nadal and Federer's clashes so special was always how unpredictable they were, as fans could never guess who would come out on top.

Though, over in the women's section of the game Serena Williams was more or less dominant, in the men's there was less confidence on who would win.

Many supporters would often point to football's Lionel Messi and Cristiano Ronaldo as a similar type of rivalry, with Nadal and Federer also being two tennis legends who emerged in the same era.