But Horford stepped awkwardly as he reached the sideline , and it was ruled that his left foot landed out of bounds .
Forward Al Horford grabbed an offensive rebound and attempted to clear the ball by dribbling to the sideline .
Forward stepped awkwardly as Al Horford reached the sideline , and it was ruled that Al Horford 's left foot landed out of bounds .
Forward Al Horford grabbed an offensive rebound and attempted to clear the ball by dribbling to the sideline .