The promising college hoopster fatally gunned down by a stray bullet in Harlem over the weekend had dreams of playing for his hometown Knicks, his tearful grandma told The Post on Wednesday.

“OMG, since 10 years old,” Patricia Smith, 71, said of her slain grandson, 21-year-old Darius Lee.

“He had one more year of college,” Smith said. “On his way onto the Knicks. He was a good kid. Everybody would tell you.

“He’s well known as Darius Lee, number 23.”

Lee was among nine people shot in Harlem early Monday at a party hosted by local rapper Troy “Rich” Rhymer — and the only to die from his wounds.

Lee was pronounced dead at Lincoln Medical Center, while others were treated at Harlem Hospital for non-life-threatening injuries.

Police have yet to announce a motive or identify suspects in the shooting.

Lee, a former standout at St. Raymond High School for Boys in The Bronx, went on to play for SUNY Sullivan Community College in upstate New York before being recruited by Houston Baptist University in Texas, where he played before he was killed.

His grandmother said Lee’s mother, who lives in Albany, was expected to return to Harlem this week as the city mourns her son’s senseless death.

“They’re supposed to make funeral arrangements today,” Smith said.

“This is where Darius stayed at most of the time, with me,” she said of the Harlem apartment building where mourners have gathered since the tragic shooting. “Everybody here is family in this building.”