Cal Ripken Jr.'s Iron Man streak is now his second-most awesome feat ... 'cause the MLB legend says he was able to beat prostate cancer in a matter of weeks!!
The 59-year-old told reporters Thursday he was diagnosed with the disease way back in February ... but, thankfully, he says he's been cancer-free since March surgery.
"The cancer was all contained in the prostate, they did a pathology report afterward and confirmed that that was the case," Ripken Jr. said.
"I’ve since had a three-month test to see if my PSA was undetectable and it was, so we can make a case that all the cancer was contained and it’s all out now."
Ripken Jr. says he was initially going to keep everything private ... but after realizing going public with his experiences could help others have similar success with the illness, he let it "slip out."
"I wouldn’t say the Iron Man contributes to it, but I was the kind of person who was thinking, ‘OK, I’ll just keep this a secret,'" Ripken Jr. said.
"But the longer you deal with it and you understand the outcome has been favorable and positive, the reason I’m letting it slip out now is I want to use the opportunity to help other people who struggle with that decision and encourage other people to go get their regular exams, get their tests."
Ripken Jr. -- who says he didn't need any chemotherapy or radiation treatments -- says he's feeling great now ... adding everything was "caught early and contained.”