For most of Doc Rivers' tenure as Celtics head coach, rookies have been no more than glorified spectators with front row seats. Like most coaches, Rivers needs to see more than just talent.
He has to see trust; specifically, trust among teammates.
For first-year players on veteran, championship-focused teams like the Celtics, that's not something that comes about automatically. It takes time which is why the rookies that ultimately contribute in their first year for the C's, usually begin the season at or near the end of the bench before working their way up into a meaningful role.
Last year at this time, nobody knew who Greg Stiemsma was other than the Celtics' brass who were simply looking for another warm body to get them through training camp.
Injuries and opportunity collided, which paved the way for the then-26-year-old rookie to play and parlay that chance into a two-year deal with the Minnesota Timberwolves.
There will be at least five rookies in the C's training camp later this month looking to have their own Stiemsma experience. That includes first-round picks Jared Sullinger and Fab Melo, along with second-round selection Kris Joseph who played at Syracuse University with Melo.
They will be joined by a couple of summer league standouts in Jamar Smith and Dionte Christmas.
While it's pretty clear that all of them will start off buried deep on the depth chart, it's not a stretch to think that at least one will emerge and help the Celtics some this season.
Who will it be?
As much as this Syracuse grad would love to toss out Joseph or Melo as the rookie to see the most action this season, that scenario is unlikely to happen.
The best rookie for the C's this season will be Jared Sullinger.
His play in summer league got many in Celtics Nation excited about his potential with the Green Team.
The most impressive thing about Sullinger never made its way on to the stats sheet. His court awareness maybe more than anything else, is why he has the best chance of any of the Celtics rookies of playing right away.
Despite questions about his size (6-foot-9, 265), one thing that's not an issue is his high basketball IQ. It is an intangible quality, but one that's pretty apparent in Sullinger when you watch him play.
At times, he'll draw contact on plays when he doesn't really have much of a chance at making the shot.
He's able to position himself for tip-out rebounds when he can't get good enough position to corral it himself.
There will be possessions when he'll ask for the ball on the post, get it, and recognize a double team before it comes and find an open teammate. He understands how to set opponents up for him to score, and he's wise enough to recognize when the pass is there to be made.
Those are the kind of plays that Sullinger is capable of making when given an opportunity, but seldom seen while at Ohio State because that wasn't necessarily the role they needed him to play.
"I can pass the ball," Sullinger said. "Score, rebound, pass, defend, whatever the team needs me to do, that's what I'll do. That's how I've always played."
From the days of Red Auerbach roaming the sidelines to the "Ubunto" era, doing "whatever the team needs" has been part of the foundation of all the great Celtics teams.
While that alone gives Sullinger a shot at playing early, he will also be motivated by the fact that so many teams passed on him on draft night in part because of concerns about his back.
Considered a lottery (top-14) talent, Sullinger fell to the C's who snatched him up with the No. 21 pick.
"I preach to the players it's not where you go, but being in the right fit," said Sullinger's agent, David Falk. "You wouldn't expect a player of his caliber to go 21. I think he's in a great situation. I'm thrilled that he's here. A lot of teams will regret they were intimidated by a lot of the information that was floating around about not drafting him."
For Sullinger, ultimately his play will come down to being ready when opportunity presents itself.
If you play for the Celtics and you are a big man, sooner or later a shot at playing time will come your way.
In recent years, the C's have seen their share of setbacks and injuries to post players that has ranged from a player missing a game here and there, to others being out for extended periods of time.
When those times roll around, players like Sullinger will be called upon -- and expected -- to contribute.
For a rookie, that's all you can ask.