Jason McElwain -- the former basketball manager who went viral in 2006 after suiting up and scoring 20 points in a high school game -- broke nine ribs in a serious bicycle accident Monday afternoon ... but luckily, he was wearing a helmet, and is expected to make a full recovery.
According to USA Today, police in Greece, New York responded to a call of "a bicyclist who made contact with a motor vehicle."
The 34-year-old was transported to an area hospital ... where he was treated for non-life-threatening injuries.
A spokeswoman for Strong Memorial Hospital confirmed Jason is listed in guarded condition at the facility ... meaning his status is extremely serious with an uncertain outcome.
Jason's brother, Josh, said he suffered 9 broken ribs, a broken scapula, and a punctured lung ... but he did not sustain injuries to his head or back, fortunately.
Josh said he's thankful Jason was wearing his helmet at the time of the accident ... fearing things could have been much worse for his brother.
Jason, who is autistic and now works as a motivational speaker, had one of the most memorable games ever as a senior at Greece Athena High School in 2006.
The teen scored 20 points in the team's final home game -- hitting 7 of 13 shots and channeling his inner Ray Allen, hitting 6 threes, earning him an ESPY award that year for best sports moment.
Josh says Jason is "not in pain" and is in good spirits ... but he will remain in Strong's Intensive Care Unit for about a week before kickstarting his lengthy road to recovery.