"There were a lot of reasons why I chose Saint Louis, but more than anything I just felt it was the best fit for me," Gordon told ESPN. "Staying home will help me a lot."
He also posted his choice on Twitter on Wednesday.
Gordon, a Saint Louis native who plays at Webster Groves High, is believed to be the highest-ranked player to commit to Saint Louis since Larry Hughes, who was a McDonald's All-American in 1997 and went on to earn National Freshman of the Year honors with the Billikens in 1998.
"I talked to him the other day, and it's been a long, long time since the top guys in the city stayed home," Gordon said. "I'm hoping this starts a trend."
Gordon averaged 20.0 points and 12.0 rebounds during the first half of his sophomore season before transferring to Webster Groves. Gordon then put up 10.5 points and 6.2 rebounds playing up an age group with MoKan Elite on the Nike EYBL circuit.
This will be the second consecutive class in which Travis Ford has reeled in a ranked prospect, after he nabbed Jordan Goodwin (No. 57) in the 2017 class. Prior to Ford taking over in the spring, the Billikens hadn't picked up a ranked prospect since the ESPN recruiting database started in 2007.
"Coach Ford and (assistant) Corey Tate were also huge reasons why I want to play at Saint Louis," Gordon said. "Coach Tate is a close family friend and he's a great mentor."