If you've been watching the Celtics for any length of time, you have a pretty good idea of what Avery Bradley brought to the team this year. Excellent defense is the obvious thing that comes to mind. His reputation as an elite defender is evidenced in his top-6 finish for NBA defensive player of the year this season. Celtics.com named him Boston's defensive player of the year, and Damian Lillard even called him "the best perimeter defender in the league."
Now, the advanced statistics don't always look kindly on Bradley. ESPN's defensive real plus-minus shockingly ranks him 42nd in the PG category, and his opponent FG% differentials aren't mind blowing. I'm big on fancy stats, but sometimes the nerds are wrong. Just look at Nate Silver's last six months for example. Bradley's incredible quickness and aggressiveness pass the eye test. Combined with the glowing reviews from other players and coaches, I'm confident in ignoring stats when it comes to his defense.
Offensively, Bradley was best when he was off the ball. He's a great cutter, and makes teams pay for losing sight of him. His shooting is a key component to Boston's offense as well. Other than Thomas, he's the only guard on the team that can consistently make threes. This is huge for spacing the floor. Pulling his defender away from the paint allows Isaiah Thomas to drive to the rim easier. Boston really struggles when teams are able to pack the lane and prevent driving. Bradley opens things up a bit and helps the team run more efficiently on offense.
But his importance to the Celtics goes beyond the career high 15.2 PPG he scored this season or the spacing he provided. Bradley brings an element of stability to their lineup. The series against the Hawks showed the problems Boston faced without him.
The On/Off measure on Basketball Reference gives an interesting look at Bradley's impact on the team as a whole this season. With Bradley on the court, Boston scored 109.8 points per 100 possessions, compared to just 101 without him. This differential of 8.8 points is actually the highest on the team. Obviously there are other factors. He shares a lot of minutes with Isaiah, so there's some overlap there for sure.
However, there were plenty of times this season where Stevens used lineups consisting of Bradley and four bench guys. Given Boston's noticeable struggles without Isaiah Thomas on the floor, you would expect this group to falter offensively. But in just over 400 minutes, Boston had a 109.9 offensive rating and a 102.1 defensive rating when Bradley was on the floor without the four most common starters. (Thomas, Crowder, Johnson, Sullinger, per NBA wowy). That might not seem like a huge sample of minutes, but these stretches matter during the game. Posting a scoring differential that high without the majority of your starters is a nice bonus for a team. Evan Turner got plenty of deserved love for his impact on the bench unit this season, but Bradley played an important part too.
Avery Bradley has his limitations. He can't really rebound and doesn't create a ton of offense for himself. But he's a consistently good two-way player on an absolute bargain of a deal. He's the longest-tenured Celtic, and Stevens has always praised his game. Bradley may not be the straw that stirs the drink, but he's vital to what the Celtics are building.