Watch: Young Celtics fan asks coach Stevens why Thomas was traded

One Boston Celtics fan has yet to come to grips with the fact that Isaiah Thomas is no longer part of the team.

During a Q-and-A session at the Basketball Hall of Fame on Friday, Celtics head coach Brad Stevens was asked by a young boy, Shane, why Thomas was traded to the Cleveland Cavaliers.

"What he did in Boston the last two-and-a-half-years has been incredible. I said earlier what he's meant to me, what I think of him, how great he's been in the locker room, what kind of teammate he's been," Stevens said, "and those are really, really, really hard decisions. That's the hard part about being a professional basketball coach.

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"I’ve stared at the wall many times and thought, man, having guys in college for three or four years and knowing exactly when they’re going is a pretty good way of doing things."

Thomas was only with the Celtics for under three seasons, but made quite the lasting impression during his stay, landing on two All-Star teams and the All-NBA second team in 2016-17, a season in which he led Boston to first place in the East with a 53-29 record.