Isaiah Thomas is 5-9. Trevor Ariza is 6-8. David, meet Goliath. 

In an exhibition game pitting Seattle Pro-Am against Drew League on Friday night, Thomas blocked Ariza's dunk attempt at the rim and made the crowd go wild.

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Potential dunkers beware: Thomas will be patrolling the paint for the Celtics next season. (Someone has to do it, and it won't be Kelly Olynyk.)