Paris, France - Tennis star Rafael Nadal revealed he is unlikely to play the US Open as he dropped his strongest hint yet that his career could very soon be at an end.

Nadal and Carlos Alcaraz's crowd-pleasing run in the men's doubles at the Olympics came to an end with a 6-2, 6-4 loss to American fourth seeds Austin Krajicek and Rajeev Ram.

The 14-time French Open champion gave a lingering wave to all sides of Court Philippe Chatrier, but it seems very likely not to be just Roland Garros that does not see Nadal on the court again.

Asked whether he would head to the US, where events building up to the US Open are already underway, the 38-year-old said: "It looks like not, but I'm going to let you know soon. For me now, I can't give you a clear answer, I need some time. But for me, it looks difficult."

Answering a question about his relationship with Alcaraz, meanwhile, Nadal cast even more doubt on his future.

"If my age would be 10 years less, we were going to create a beautiful relationship on court and we were going to share a lot of beautiful moments together," he said.

"But that's not going to happen. We'll see if I keep playing the normal tour. But of course, I will be supporting him from home and wishing him all the very best every single time. Even if I keep playing or not, I love tennis.”

Nadal has signed up for the Laver Cup in Berlin in September, and two years after Roger Federer bade farewell at the Ryder Cup-style event, there is a possibility his great rival may follow suit.

He had hoped to sign off his Olympics career with a third medal, having previously won gold in singles and doubles, but a passionate crowd was unable to get him and Alcaraz over the line against a quality doubles team.

"It was disappointing to not bring back a medal for Spain, but that's it," said Nadal.

"I tried my best in every single minute that I was on court, but it was not enough to achieve our goals.

"If that's the last time, it's an unforgettable feeling and emotions. They give me the love and the support every single second that I have been on court. It's super, super special to feel that in particular in this place.

"At this stage of my career, I play for feelings; I play for emotions more than for results.

"I won enough in my career, much more than what I ever dreamed. For me, it's about enjoying different experiences, and that's another lifetime experience, to share with Carlos, an amazing player who I think is going to be, of course, one of the best of the history of this sport."