"He was like a big brother to me, a friend" - Stan Wawrinka on Roger Federer

Stan Wawrinka, just like many Roger Federer fans across the world, shed tears on that fateful day in September when the Swiss maestro decided to hang up his racket after a fruitful and illustrious career.

Wawrinka considered his compatriot a "big brother" and a "friend," making it difficult for him to process the 20-time Grand Slam champion's retirement.

"I cried for Roger (Federer). It was hard, a strong feeling. Even talking about it is difficult. When I came on the tour, he was already there. He was like a big brother to me, a friend," said Stan Wawrinka on the RMC podcast Court No. 1 as mentioned in an article on Eurosport.

Wawrinka debuted on the tour in 2002, four years after Federer did. They donned their country's colors together in the Davis Cup across various ties over 10 years (2004-09, 2011-12, 2014-15), partnering for doubles five times in 2008, 2011-12, and 2014 (twice).

They won four of those, losing only against the USA's Mike Bryan and Mardy Fish in the World Group first round in four sets in 2012.

Together, they took gold in the doubles competition at the 2008 Olympics.

Roger Federer (right) hugs doubles partner Stan Wawrinka (left) after winning his only gold medal in the Olympics in 2008.

"Luckily, there weren't any cameras in the hallways or locker rooms back then" - Stan Wawrinka recalls incident when Roger Federer's wife Mirka called him a 'crybaby'

Roger Federer and Stan Wawrinka share a light moment during their doubles match at the Davis Cup Finals in 2014.

Recently, Stan Wawrinka hogged the headlines for calling eventual Paris Masters champion Holger Rune a "baby" for his on-court attitude during their first-round encounter, which the Swiss lost after squandering three match points.

But years back, it was Wawrinka who was on the receiving end of a "crybaby" comment made by Roger Federer's wife Mirka during the duo's semifinal clash at the ATP World Tour Finals in 2014.

While Wawrinka's fiery words against Rune during their post-match handshake were captured on video, the three-time Grand Slam champion was happy that it was not that way at the season-ending championship in London eight years ago.

"Luckily, there weren't any cameras in the hallways or locker rooms back then," Stan Wawrinka told the RMC podcast Court No. 1 as mentioned in the same article on Eurosport.

Stan Wawrinka (left) and Roger Federer (right) after their semifinal match in the ATP World Tour Finals in 2014

"It was a critical moment, very complicated. The situation was difficult for both of us to handle," added Wawrinka.

Wawrinka and Federer settled the matter privately in the locker room after the match.

A week later, the good friends rekindled ties as they displayed their rapport on the court anew, teaming up in doubles to help give Switzerland its first and only Davis Cup title.

Federer may have called time on his career, but there's more left in the tank for 37-year-old Wawrinka, who still has the belief that he can go toe-to-toe against the best players.

"If I no longer had the feeling that I could beat the best tennis players, I probably would have stopped. It's important for me to be competitive, I keep playing because I want to experience the matches, the big challenges," said Stan Wawrinka.

Wawrinka has compiled an 8-14 record this season, logging his biggest wins against Daniil Medvedev, Casper Ruud, Frances Tiafoe and Reilly Opelka.