'My hands trembled on match point' - Del Potro recalls USO 2009 win over Roger Federer

In the second part of a candid chat with ESPN, Juan Martin Del Potro talked about his maiden Grand Slam title at 2009 US Open - where he beat Rafael Nadal in the semifinal and five-time defending champion Roger Federer in the final.

Roger Federer and Juan Martin del Potro have clashed 25 times in their careers, often with high stakes on the line. And the Argentine's biggest career achievement was also one of the biggest disappointments of the Swiss' career. Yet, there remains a rich bond of friendship between Federer and Del Potro.

In the US Open 2009 final, Del Potro had rallied from a set and a break down to defeat then-world No. 1 Roger Federer in five sets, in what was his first ever win over Roger Federer after tasting defeats at Australian Open and French Open during the same season.

#TENISxESPN El hermoso regalo que @delpotrojuan le hizo a su abuelo. 😢 https://t.co/Dm85YgzwKA

— ESPN Tenis (@ESPNtenis) June 18, 2020

The same thing as Roland Garros couldn't happen again: Del Potro recalls the jitters during US Open final

In the first part of the show, Del Potro had spoken in detail about his disappointment at failing to beat Roger Federer at Roland Garros 2009 despite having had him on the ropes throughout the match.

"I felt inside me that it was the opportunity to win my first Grand Slam and I had let it pass. That match hit me a lot, I felt like a loser," Del Potro said of his ordeal in Paris, as he lost in five sets to the eventual champion Roger Federer.

Months later, Del Potro would face the Swiss Maestro again at Flushing Meadows. And as that match showed, Del Potro had learned from his mistakes; when he saw Roger Federer tiring, he made sure he shut the door on him.

Roger Federer and Juan Martin Del Potro embrace at the net

"He is always intact, but when I realized that he started hitting the racket frame, I knew he was tired because he stopped moving. He no longer had clean contact with the ball, and to beat the best you have to grab those details," the Argentine said.

After more than four hours, the moment finally arrived and Juan Martin del Potro had Championship Point as he led Roger Federer 5-2 in the fifth set. Speaking of how he felt at that juncture, Del Potro said:

"There was noise, a lot of people screaming, I saw 'Championship Point Del Potro' and my legs automatically loosened. My hands trembled and I said, 'The same thing can't happen to me as it did in Roland Garros'."

Roger Federer is an example both on and off the field: Juan Martin del Potro

The Match in Africa: Roger Federer v Rafael Nadal

The friendship and mutual respect between Roger Federer and Juan Martin Del Potro are well-known in the tennis community. But unbeknownst to many fans, the roots of this friendship were laid when Juan Martin Del Potro received a wildcard at 2006 Basel Open thanks to Roger Federer.

#TENISxESPN Respeto y admiración: así es la relación entre @delpotrojuan y @rogerfederer.*https://t.co/aVxTUe8yt4

— ESPN Tenis (@ESPNtenis) June 18, 2020

"It is a pleasure to talk to him many times. He is an example on and off the field," Del Potro said of the 20-time Grand Slam champion.

The Tower of Tandil also complimented Roger Federer's ability to keep his feet on the ground at all times despite being such a big icon in the sport.