Bollettieri has coached the likes of Andre Agassi, Tommy Haas, Jim Courier, Marcelo Rios, Martina Hingis, the Williams sisters and Maria Sharapova from his school.
The American told a press conference recently that Rios was the most talented of the lot.
"He was undoubtedly the most talented of all the tennis players that I've had", he told ESPN.
Ríos is a former World No. 1 tennis player and became the first Latin American player to reach the top position on the ATP singles rankings in 1998.
He was the first player to win the three clay-court Masters Series tournaments (Monte Carlo, Rome, and Hamburg) since the format began in 1990. He is the only male player in the open era to have been World No. 1 while never managing to win a Grand Slam singles tournament in his career. He did reach the 1998 Australian Open final, losing to Petr Korda.
He retired prematurely in 2004 due to a back injury. He played his last ATP level tournament while only 27 years old at the 2003 French Open.
Bollettieri also talked about the quality of the United States tennis players today.
The coach said the reason for the weakness in American tennis nowadays was due to the increased attention that his country has reserved for sports like baseball, basketball, football, and the great growth of tennis in other countries such as Serbia, China, Croatia and Japan.
"I try to produce champions, but I also try to prepare children for the risks of life," said the coach.