Marat Safin retired because he knew he couldn't compete with Roger Federer, Novak Djokovic, and Rafael Nadal, he has revealed.
Safin is arguably one of the greatest under-achievers in tennis despite reaching world number one and winning two Grand Slams.
All of that was achieved in his early 20s, though, and as he began to battle injuries and his ranking slipped, the dominance of the Big Three was starting to take hold.
And, after seeing what was coming and how he was not going to be able to join them, he opted to simply walk away instead.
“In this sport you are either in the top five or you are nowhere," Safin told the Russian press.
"I didn't want to continue playing tennis as a world number 11, 12 or 20.
"Playing with young tennis players, getting tired and running with a very sore knee only discredits you.
"I have always believed that it is best to stop playing sports before the sport leaves you.
"If my knee hadn't bothered me so much, I could have played for a few years, but I was already tired of this world. I was bored.
"I had no motivation and started losing to unknown players.
"If you can't beat players like Federer, Nadal or Djokovic anymore, why continue?"
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