If we’ve learned anything over the first two weeks of this helter-skelter season, it’s that trends are developing at a rapid rate. One week you’ve got everything figured out, and the next teams are searching for answers to questions they didn’t know they had.
Like, for example, the recent Celtics  habit of playing poor offensive first halves . “Don’t know,” coach Doc Rivers  said when asked for an explanation. “If I could, I would explain it to them first and then I would try to work on it. Then, I hopefully wouldn’t have to answer this question.”
The Celtics scored just 34 points against the Nets  on Wednesday and then, as Rivers said, set the game back a half-century with a dreadful 25-point showing against the Pacers on Friday, tying a franchise record for offensive futility.
In both games a pattern emerged: The starters began with a decent, if underwhelming, start and the second unit couldn’t provide any offensive support.
Against Indiana, they scored 10 points in the first six minutes. At the end of the first quarter, they had 14 points on the board, and it stayed that way for the first three minutes of the second quarter before Rajon Rondo  and other starters checked back in.
It was a similar story the previous game against New Jersey. The difference on Wednesday was the reserves clamped down defensively against a Nets team that was missing its two best players and didn’t allow them to score. The Pacers are not the Nets, and while they didn’t run away with the game in the first half, they established a lead and forced the Celtics to play catch-up all night.
Small sample sizes abound, but there’s another trend developing through the first eight games. With one exception, every successful lineup the Celtics have used  this season has included at least three of the four All-Stars. (The exception: Rondo, Allen, Marquis Daniels , Brandon Bass  and Jermaine O’Neal , who have been their most productive lineup ).
Not that this excuses the starters, who haven’t been nearly as efficient as they had been in the three previous wins against the Wizards and Pistons. Paul Pierce  had a rough game on Friday, shooting just 3-for-17 with five turnovers. This was one game after Pierce poured in 24 points and helped them overcome Ray Allen ‘s absence. Pierce is Pierce. He’ll bounce back, as will the starters who have been playing together for more than four years.
The second unit is essentially brand new. With the exception of Daniels, Rivers is integrating five completely new rotations players in Bass, Keyon Dooling , Chris Wilcox , Greg Stiemsma  and Avery Bradley , who is getting the first regular minutes of his career.
There’s hope that Mickael Pietrus  can make his debut this week. Pietrus had offseason knee surgery but has looked good in workouts, according to several observers. He’s a career 36 percent 3-point shooter and takes almost half his attempts from behind the arc. Pietrus isn’t a savior, but the Celtics desperately need that deep-shooting threat and his versatility on the wing.
The concern, as it has been since Danny Ainge hastily (and rather ingeniously ) cobbled together this second unit, is that there simply isn’t enough scoring. The reserves are shooting just 42 percent from the floor and 31 percent from 3-point range and their offensive efficiency ranks 25th per HoopsStats .
“That’s on me,” Rivers said. “I’ve got to find something I can give them. They’re an energy group. They’re not a scoring group. We’ve got to come up with something. That’s not on them.”
On Friday, Rivers took Dooling aside, and the veteran guard has already become a trusted source of basketball ideas. They returned to the same notion that Dooling has had since the beginning of camp: The second unit needs its own identity. They’re not the starters. They don’t have the same skill-sets, especially offensively where there is no one who can come close to matching Ray Allen and Pierce’s shooting abilities.
A major part of their struggles has been a lack of practice time. That’s a given, but it shouldn’t be taken for granted both offensively and defensively where schemes have to be implemented and continuity has to be developed. There was no official practice this weekend, but the reserves were expected to come in and work out on Sunday.
“It’s refreshing with this group,” Rivers said on Thursday before the team held its first practice session of the season. “They don’t look at it as punishment. This group is, what time? Keyon is the leader of it. He’ll come to you and say how about 10 o’clock or 11 o’clock. He’s been phenomenal [with] that.”
There’s a lot to work on. First, the bad news:
Spacing has been an issue without consistent shooting on the floor and Dooling has more turnovers (14) than assists (11). Rivers had Bradley bring the ball up the floor at times so that Dooling can run off screens and initiate movement and while the young guard has kept his turnovers in check, he’s not a playmaker at the point. Daniels is shooting 27 percent and he and Bradley have missed 10 of their 11 3-point attempts. Stiemsma can make a jump shot as we’ve discovered, but he is by no means a player who can create his own offense.
But there is potential here. Bass has emerged as a top-flight sixth man and is getting his share of minutes with the four All-Stars. Dooling is making 39 percent of his 3-pointers and Stiemsma (blocks) and Bradley (on the ball pressure defense) have flashed the kind of game-changing defensive ability that will be valuable for a team that will have to fight veteran legs all season. Wilcox missed three games with a shoulder injury, but he has been active on the offensive glass, a valuable skill for a team that ranked dead last in offensive boards last season. For all his struggles, Daniels has worked well with starter-heavy lineups.
Unlike past seasons when Rivers played eight, or nine players at the max, he’s using 10 and sometimes 11 players in games. It’s all part of the development process for a team that has barely begun to play together. There’s time to make it all work, but it’s been an uneven beginning for the reserves.