Juan Martin Del Potro admits his career could be over after his latest injury nightmare.

The Argentinian fractured his right kneecap for the second time in eight months after slipping during his win over Denis Shapovalov at the Fever-Tree Championships.

The world number 12 will undergo surgery in Barcelona on Saturday and says he does not know whether the match at Queen's Club, which he won 7-5 6-4 before pulling out of his scheduled second-round clash with Feliciano Lopez, will be his last.

He said on Instagram: "As you might know I fractured my right patella once again. After medical studies and talking to the doctors they said surgery was the best treatment.

"I had asked them for the best option health-wise, not just for tennis. They said surgery, no doubt about it.

"As you can imagine this is a tough moment, it's sad to go through all this once again. I didn't expect this at all. But it will happen tomorrow.

"I cannot say anything more than that. I don't know what will happen next. Hopefully I will have a good recovery. I hope my knee can heal properly.

"If that match was the last of one my career, that I don't know. During rehab I will be able to think clearly. I will know what my body is able to do."

Del Potro originally fractured the same kneecap last October, forcing him to miss the rest of the season and limiting him to only five tournaments so far this year.

The 30-year-old, who won the US Open in 2009, has been plagued by injuries throughout his career having also undergone four operations on his wrists.