Four telling numbers about the Celtics' 4-1 start

The Celtics still aren't considered an East contender yet despite a 4-1 start to the regular season, but with quality shorthanded wins over the likes of the Toronto Raptors and Milwaukee Bucks, there is a lot to like over the C’s start to the season. You wouldn’t necessarily know it by listening to Brad Stevens though.

"I just think we have to improve a lot,” the head coach said at practice Monday. “After taking a couple of days and really watching, seeing where we are, I think we've got a lot of good things going. Guys are doing a great job of staying together and finding ways. But we have to get a lot better to be what we want to be, which I think's important. You know, you look across the league, the five-game starts don't really matter. How good you are evens itself out in the end, whether you're on the good side of that or the bad side of those starts. So we just have to focus on getting better."

The areas that need improvement have been quite clear early. Boston is shooting just 41.7 percent from the field, which ranks 28th in the league overall. Without Enes Kanter, the C’s have fallen to the bottom third of the league in rebounding rate as well. The return of valuable bodies like Kanter and Jaylen Brown later this week should be a needed boost in both these areas as the team’s shooting reverts back towards the mean.

So how exactly have the C’s pieced together a 4-1 start despite those struggles? Let’s take a closer look at some telling numbers over the past two weeks and just how sustainable they can be for this group over the long haul.

122.7 offensive rating in the second half (1st in NBA): The Celtics have struggled out of the gate on the offensive end but have played like the best offensive team in the league after intermission over their first five games. With Kemba Walker, Gordon Hayward and Jayson Tatum’s shooting splits all significantly better after halftime, the C’s have been able to put together comeback wins in four straight games.

For as good as the Celtics have been in the second half, the offense has been just as dismal early in games (91.4 offensive rating ranks last in the NBA for the first half). Boston’s defense has managed to keep them in games early on (7th in first half defensive rating) but facing early deficits is a trend that Kemba Walker wants to change going forward.

“I can't really put my finger on it, honestly,” Walker said of the slow offensive starts. “It's just something we have to be conscious of, and get better at it. For us, I think our slow starts are on the offensive end and that's where it kind of gets in our heads and we start to get frustrated. We are missing shots early, I think it trickles down to our defense. We have to be better. We are not going to make shots all the time. We can't control the offense all the time, but we can control the defense and control our energy, so that's where we have to start.”

11.4 percent turnover rate (1st in NBA): The Celtics aren’t making shots, aren’t getting many offensive rebounds (22nd in offensive rebounding rate) and are an average team getting to the free throw line. So how exactly are they a league-average team on the offensive end? Taking terrific care of the ball has helped. They are getting a chance to take more shots every time down the floor due to this discipline as point guards like Kemba Walker and Marcus Smart have been sensational in limiting mistakes. This has also helped the C’s on the defensive end as they’ve been able to limit opponents to just 10.2 fast break points per game, a top-3 mark in the league. Boston was fourth in turnover rate last year so this looks like an area that is sustainable for the long-term right now, especially if Smart plays at this level. He had the worst turnover rate on the team last year (16 percent) so his strong start this year (7 percent) is very promising.

41.2 points allowed in the paint per game (2nd in NBA): The Celtics have been playing small over the last few games with Kanter sidelined. That has meant more minutes for the likes of smaller bigs like Grant Williams and Daniel Theis. Their lack of size may be a sign the C’s would be vulnerable in the paint but that’s been far from the case. Good size on the wings and strong versatility from Williams, Theis and Grant Williams have helped the C’s push out their opponents towards the perimeter in shot attempts. Theis, in particular, has shown some stellar rim protections thus far (9.8 block rate is ahead of Rob Williams) and the C’s starting five has been at its best from a defensive standpoint when he is out there. It remains to be seen how big of a role Kanter will play in the center rotation upon his return but these numbers indicate that a smaller look in the middle with more mobile bigs is the best course of action for the Celtics defense over the long haul.

33.3 percent of all 3-point field goals have been unassisted (3rd in NBA): Kemba Walker has been a master of the pull-up 3 on the pick-and-roll throughout his career but he’s getting some company on that front this year with Jayson Tatum, who is showing no hesitation at firing away from long range while taking a career-high 7.6 attempts per game. Tatum has turned most of his long 2s into 3s this season and that’s a trend the C’s will need to continue in order for this offense to be successful. His FG percentage will surely go up at the rim (an ugly 41 percent so far) but with his outside shot falling (48.6 percent from 3), the door is open for him to be an All-Star and punish defenders that sag off him.