And it all started with a successful tryout.
Guinn was put on the practice squad two days before the 2015-16 season began. Then he went so hard in practice that he annoyed some of the team's stars. But it was worth it, he said.
When Cory Calvert decided to transfer and Jake Toolson took a leave of absence — both players are now at Utah Valley waiting to play next year — Guinn was added to the roster.
"That was a great moment for me," he said.
BYU coach Dave Rose said they were aware of Guinn because the Cougars' former director of basketball operations, Cody Fueger, had helped recruit Guinn to UC Riverside when he was on that staff
"In the walk-on tryouts, what really impressed us was his diversity, his ability to do so many things in the short period of time that we saw him," Rose said.