MIAMI -- Chris Bosh was dealing with more than one blood clot earlier this year, and said Wednesday that he felt written off when Miami Heat team doctors advised him that the situation would likely be career-ending.

It's the first time Bosh has said there was more than the one known clot that was found in his calf in February and ended this past season.

Bosh made his revelations in the first chapter of a documentary that he's releasing through former Heat teammate LeBron James' "Uninterrupted" digital platform, with more episodes being planned for release every two or three days until the season begins.

Bosh said he was diagnosed with the clot in his calf on Feb. 11 after arriving in Toronto. He returned to a hospital there more than once in the next 24 hours or so for bloodwork and additional tests, including a CT scan.

"Clots were found, again," Bosh said. "My initial thoughts from it were, first of all, you have to be kidding. Secondly, this isn't real."

Bosh said that he then returned to Miami after the All-Star break and met with doctors. His 2014-15 season was also cut short at the All-Star break because of a clot that was found in one of his lungs.

"They told me that my season's over. My career is probably over. This just happened, this is just how it is," Bosh said, referring what followed after this year's finding of clots. "I felt right away that I was written off. ... If a doctor tells me, 'Hey, that's it and this is how it is' and I don't buy that, I think that I have the right to disagree with you. I know inside me I have a lot of talent and a lot of ability. And I have it. I know it have it."

Bosh has now spoken about his saga with James' platform twice, after a long podcast last week and now with the video called "Rebuilt," a documentary chronicling what Bosh has gone through with his clot issues in each of the last two seasons.

Also Wednesday, in an interview with James' longtime manager Maverick Carter that was streamed on Facebook and designed to promote the video series, Bosh said he remains in good spirits and confident that his situation will work itself out.

"We're just in the process of making sure that I can get back on the court," Bosh said.

Bosh has been back in Miami for several days after spending some of his summer in Los Angeles, and it's still unknown if he will be cleared for training camp that starts in the Bahamas next week.

At minimum, Bosh would need to pass physical exams before that clearance gets granted.

In the podcast last week, Bosh discussed a regimen of taking bloodthinners that is utilized by NHL player Tomas Fleischmann, who he connected with through their agents this summer. Fleischmann was told that his career was over when he was diagnosed with having multiple clots, but has played for several years while on bloodthinners -- either taken in pill form or through injections.

Typically, athletes in contact sports are advised to not participate when on bloodthinners because of the increased chance of internal bleeding and other complications.

Bosh wants to play this season, and is owed about $76 million for the next three seasons whether he plays or not. The Heat have not been able to comment specifically about Bosh's medical status, though Heat President Pat Riley said over the summer that the team is open to having the All-Star forward return. And recently, Heat managing general partner Micky Arison tweeted at Bosh saying that he would see him in training camp.

"If he was on any kind of preventive therapy and had another clot, then that is very problematic," Dr. Robert Myerburg, a professor of medicine at the University of Miami Miller School of Medicine, said Wednesday. "If he was not, then just the fact that he had the second one certainly increases the risk. But in terms of the strategy that's proposed, I have no experience with it. It's an unusual strategy. And basically, he and the team have to make a decision of risk versus benefit."