Parker, 22, was thrown off an inner-tube being pulled behind a boat in the Morse Reservoir north of Indianapolis, according to multiple reports. Parker never resurfaced.
"We are extremely saddened with the news of Dai-Jon's death," Vanderbilt Coach Kevin Stallings said in a statement. "Everyone who watched him play basketball knew what kind of athlete he was. But, to those of us who knew him and loved him, he was as good and happy of a person as you would ever meet. He always had a smile on his face and I will always remember him for that smile and the positive spirit he had. We send our deepest condolences and prayers to his family, friends, and others who were lucky enough to have met him. The Vanderbilt basketball family will miss him."
Parker played in 92 games for the Commodores over three seasons. As a junior, he started 26 games and averaged 8.3 points with 4.4 rebounds and 3.2 assists per game.
He was not allowed to return to Vanderbilt for his senior season because he was unable to maintain the standards of the Commodore program both on and off the floor, Stallings announced in a release in August.
Parker ultimately transferred to the University of Indianapolis, a Division II program, for his final year of eligibility. He started in 31 games for the Greyhounds, averaging 9.4 points per game.
Parker, a Baton Rouge, La., native, was a four-star recruit coming out of Milton (Ga.) High School in 2011.