They have a young, defensively tenacious team that seems tailor-made for the modern NBA. The only problem? They struggle to make shots.Boston hit just 34.6% of its catch-and-shoot threes last season, second-worst behind the hapless Lakers. Simply put, the Celtics have a bunch of three-and-D guys who haven't quite grasped the three part yet.
The biggest improvements need to come from Jae Crowder and Marcus Smart. The 6'6" Crowder shot 33.6% from deep, which means he's close to becoming a reliable stretch option. He's otherwise skilled on offense and so good defensively that a three-point stroke would likely make him an All-Star. Smart is arguably the team's best defender behind Avery Bradley, but he shot a ghastly 25.3% from beyond the arc last year.
Bradley can serve as a model for his teammates. He's increased his volume of outside shots in each of his six seasons and for the most part has maintained his efficiency, putting up a solid 36.0% career mark. If Crowder can be that accurate and Smart can surpass 30%, Boston could have an offense to match its top five defense. And that would put the defending champs on notice.
PROJECTED LINEUP | 2015--16 stats
COACH BRAD STEVENS (4th season with Celtics)
2015--16 RECORD 48--34 (2nd in Atlantic)
PG ISAIAH THOMAS
22.2 PPG; 6.2 APG; 42.8 FG%; 35.9 3FG%
SG AVERY BRADLEY
15.2 PPG; 2.1 APG; 44.7 FG%; 36.1 3FG%
SF JAE CROWDER
14.2 PPG; 5.1 RPG; 44.3 FG%; 33.6 3FG%
PF AMIR JOHNSON
7.3 PPG; 6.4 RPG; 1.1 BPG; 58.5 FG%
C AL HORFORD*
15.2 PPG; 7.3 RPG; 3.2 APG; 50.5 FG%
PG MARCUS SMART
9.1 PPG; 4.2 RPG; 3.0 APG; 34.8 FG%
PF JONAS JEREBKO
4.4 PPG; 3.7 RPG; 41.3 FG%; 39.8 3FG%
C KELLY OLYNYK
10.0 PPG; 4.1 RPG; 45.5 FG%; 40.5 3FG%
TELLING NUMBER 34.6
A rival scout sizes up Boston
Al Horford is a really, really big upgrade for them. He's a little older  and has a few more miles on his legs, but he fits the way they want to play. He'll improve their defense and he's also an offensive threat—not so much in the post, but in the pick-and-roll. He's a good 18-foot shooter, a playmaking center. They didn't have that in Jared Sullinger [who is now with Toronto].... I think Amir Johnson will start, but they have the option of moving Jae Crowder to the four and playing Marcus Smart, Avery Bradley and Isaiah Thomas together as a small team that'll be really good defensively. That's a great option.... Thomas has a great ability to get into the lane and use his body. He's only about 5'9", but he's got long arms with big hands, big shoulders and he can really challenge the bigs. I'm always amazed at some of the stuff he can do when he takes it to the rim. And he's a knock-down pull-up shooter.... If Smart improves his shooting he can be the player that everybody thinks he can be. That's always going to be his Achilles' heel. He's strong, great size for a point guard, really can defend. If he comes out [playing] well, there are a lot of options they have with that loaded backcourt—I mean in the way they play and also in assets to make a trade with their high picks.... Crowder has to take another step. He's a good player and can lock down threes but I'm not convinced that he is their small forward of the future. [Rookie] Jaylen Brown, maybe, will be.... Brown will play. He's not a very good shooter, but because he's good defensively and he can run and has good size [6'7"], he'll get minutes.
Anything short of a conference finals berth would be a disappointment.