After shedding a few more veteran contracts and largely standing pat in free agency, the Boston Celtics have clearly moved into the second phase of their post-Big Three rebuild.
However, it isn’t enough for the C’s to just keep acquiring young pieces and letting older players go. These new, unproven players must step up and establish themselves as assets to build around.
Outside of Rajon Rondo and—for better or worse—Jeff Green, the Celtics roster is filled with unknown commodities.
Rookies Marcus Smart and James Young should see playing time right away, while Boston is eager to see if players like Avery Bradley, Jared Sullinger and Evan Turner have yet to reach their ceilings.
The Celts aren’t going to win the 2015 title, but if they want to at least be a competitive NBA team, they need several players to take a serious leap.
Without further ado, let’s look at a few possible candidates.
After costing himself millions of dollars during his ghastly stint with the Indiana Pacers, Turner joined the Celtics hoping to prove himself.
It’s a low-risk, high-reward move for Boston that could prove savvy if Turner ever capitalizes on the potential he showed in college and with the Philadelphia 76ers.
In 2013-14, Turner averaged 14 points, five rebounds and 3.2 assists on 42.5 percent shooting from the floor.
Unfortunately, those numbers plummeted to 7.1 points, 3.2 boards and 2.4 assists on 41.1 percent shooting in Indiana, and he was a complete non-entity during the Pacers’ playoff push.
Turner is a gifted athlete and has legitimate starter upside, but he’s also a shaky shooter and uninterested defender.
Given that Green (1.7 assists per game) didn’t turn heads as a secondary playmaker, Turner’s passing ability could be a real asset.
He is capable of handling the ball from the 2 and 3 positions, and he could be a nice complement to Rondo in that regard.
Turner actually played better as a forward last season than as a guard. His player efficiency rating at the 2 was just 11.8, but he posted PERs of 13.8 and 16.5 at the 3 and 4 spots.
Turner will likely begin the year coming off the pine, but if Green or Bradley really struggles, then he could be elevated for a starting role.
He’ll need to improve as an outside shooter, though, as Turner has knocked down just 32.6 percent of his three-pointers for his career.
Still, it’s easy to forget that Turner is just 25 years old and has been in difficult situations with Indy and Philly. He has a real chance to step up and become an impact piece for Boston.
To put it simply, the 2014-15 Celtics are shaping up to be a squad of bricklayers.
Last season, Boston was just 27th in the league in three-point percentage at 33.3. That number must increase if the C’s hope to be a competent offensive team.
Unfortunately, it is unlikely that Rondo, Smart or Turner is going to morph into even a league-average outside shooter.
Bradley is solid from the corners, and Young has upside, but neither is going to be a volume gunner.
In fact, Thornton may actually be Boston’s most consistent shooter.
He had a down year from outside in 2013-14, canning 34.5 percent of his triples, but shoots a career percentage of 36.1.
As you can see from his shot-chart heat map (below), Thornton is a legitimate threat from anywhere beyond the arc.
Thornton struggled with the Kings but was rejuvenated on the Nets, averaging 12.3 points and stroking a solid 38 percent from distance.
At 6’4”, Thornton doesn’t have great size to defend starting 2-guards, but he could thrive as a sixth man off the bench.
Obviously, if Thornton struggles with his jumper and Smart emerges early, Thornton could find himself buried, but if he shoots well from outside, he could be a legitimate factor.
The only pure center on Boston’s roster, Tyler Zeller has a shot to be an impact piece right away.
While Jared Sullinger and Kelly Olynyk are both skilled offensive bigs, neither one runs the floor or plays in the paint as well as Zeller.
He had a bit of a down season in 2013-14 playing behind a healthy Anderson Varejao but has solid career averages of 6.9 points, 4.9 boards and 0.9 assists on 47.2 percent from the field.
Brad Stevens sang Zeller’s praises to ESPNBoston’s Chris Forsberg, saying: "A guy with his skill can score on the block but also stretch the defense and has enough handle and savvy to play facing the basket. And you can kind of play around him—not too dissimilar from some of other big guys that we have now."
Last season, Zeller posted a 16.2 PER at center, compared to a 14.4 PER at power forward, proving that he is a more consistent force at the 5.
He isn’t an elite floor stretcher or post scorer, but Zeller can hit mid-range shots if left open and has a decent hook with either hand.
As mentioned earlier, he’s great running the floor and scoring in transition, which is an asset for any big man playing alongside Rondo.
Defensively, he isn’t going to block a ton of shots, but he knows where to be, rotates well in the paint and uses his length to bother opponents.
The downside with Zeller is that at 24 years old and with a full college career under his belt, he may never be more than a quality backup, but it’s worth taking the risk and finding out.
Boston may opt to start the Sully-Olynyk frontcourt pair for scoring reasons, but if Olynyk really struggles on the defensive end, expect him to be replaced by Zeller early.
Sullinger probably possesses the most upside of any returning Celtic and is a lock to be a starter after shuffling between the starting five and the bench for his first two years.
Sully made some real strides last season, averaging 13.3 points, 8.1 boards and 1.6 assists, but connected on a mere 42.7 percent of his shots and 26.9 percent of his three-pointers.
As a stretch 4, Sullinger could be a matchup nightmare, but he needs to bump that shooting percentage up to at least league average.
ESPNBoston.com’s Chris Forsberg noted that Sullinger appears to have slimmed down and looks to be in better shape than he was last season.
My biggest thing was health last year. I think I was a little afraid at the beginning of training camp, due to my back, the contact and all of that stuff. I was afraid what was going to happen in the middle of the season. But now I know what I can do, I know my back is going to hold up and, the beautiful thing about it is, that I have another year to show who Jared Sullinger can be.
Sullinger is still at his best using his strength and size around the basket, though. He is far and away Boston’s best rebounder and has a nose for the ball rivaled by few big men.
That’s apparent from his shot-chart heat map (below), which clearly illustrates that Sully should be playing more in the paint than on the perimeter.
Olynyk and Zeller are both capable of playing further from the basket, which would allow Sullinger to go to work down low.
His post game is still progressing, but Sully has good hands around the rim and a solid fadeaway jumper.
At 6’9”, Sullinger can play some center in a pinch but is more likely to log time at the 4. If Brandon Bass ends up being dealt, Sully could easily see 34-plus minutes each night.
He’s also simply a more efficient player at power forward, where his PER was 24.3 compared to 16.6 at center.
Obviously, Sullinger’s upside will be limited if his outside shooting doesn’t improve or Boston chooses to play Bass more to build up his trade value, but he projects to be the team’s third or second option offensively.
Sully is the only Boston player besides Rondo with real All-Star potential, and if the C’s are going to be a surprise team in the Eastern Conference, the burden will likely fall on his shoulders.
Stats per 82games.com unless otherwise noted.