Kelly Olynyk

Nothing pisses off Kelly Olynyk more than a poorly run fantasy basketball league -- which is why the Boston Celtics player tore our TMZ photog a new one right in the middle of the street. Long story short ... our guy is in a league that starts the fantasy playoffs THIS WEEK. Olynyk feels that's…

Justin Bieber just got a HUGE bball endorsement ... 'cause one of Canada's biggest hoops stars tells TMZ Sports the Biebs might have what it takes to suit up for the Canucks in international play. We were at LAX when we ran into Celtics star Kelly Olynyk -- who hails from the great North -- and we…