From this Sports on Earth article about the NBA preseason:
http://www.sportsonearth.com/article/99181564/2014-15-nba-preseason-recap4. Marcus Smart is already one of the best defensive guards in the NBA.
The gushing by Brad Stevens -- and multiple teammates, including Avery Bradley, who knows what good defense looks like -- is obviously a good sign. Better than that, though, is the empirical evidence. Heading into his career, we figured Smart would be able to handle his own on defense thanks to sheer physical ability, strength and quickness. We didn't know it would come together so quickly, how effective he'd look from day one.
The No. 6 overall pick in this year's draft has yet to do anything impressive with the ball, and Stevens replaced him with Evan Turner at point guard after the team's first couple games. But defense is a different book altogether. Smart bulldozes through screens, rarely gambles and does whatever it takes to make his assignment's night unforgettable in the the most inconvenient possible way. He's a steals machine, jumping passing lanes and already showcasing the instincts of someone with All-Defensive honors all but locked up (no pun intended) in his future. No point guard across the NBA will actively look forward to facing Smart this season.