In years past, the Boston Celtics were able to win thanks largely to the play of Rajon Rondo, Paul Pierce, Kevin Garnett and Ray Allen, with any contributions from other players serving as a welcome bonus.
However, those days are gone, and the franchise's underwhelming 2012-13 season proved that this team cannot succeed if its ancillary pieces struggle as much as they did.
Boston has plenty of talented pieces on their roster capable of stepping up, but those players simply failed to do that with any sort of regularity. If this team wants to be anything more than first-round fodder in 2013-14, it is imperative that these role players either develop their games or, in some cases, regain their past form.
With the future of Kevin Garnett and Paul Pierce in more serious question than ever, here are the four players who must step up for the Celtics next season.
Note: Because of the speculation surrounding KG and Pierce, I did not place them on this list. Also, only players with guaranteed deals for 2013-14 are eligible, so apologies to Shavlik Randolph, Terrence Williams and, of course, D.J. White.
When it happened, the Celtics nabbing Courtney Lee in a sign-and-trade with the Houston Rockets for nothing more than E'Twaun Moore and a few inconsequential pieces was viewed as one of the more savvy small moves of the 2012 offseason.
However, Lee's performance during the 2012-13 campaign left plenty to be desired and has many questioning whether he has a long-term future in Boston despite having three seasons remaining on his contract.
To his credit, Lee acknowledged that his play was "inconsistent" to ESPN Boston, but that does not change the fact that Lee needs to step up his performance significantly if he wants to be a part of the Celts' future.
During the regular season, Lee averaged 7.8 points, the lowest of his career, along with 2.4 rebounds and 1.8 assists per game. He shot a career-high 46.4 percent from the field and a respectable 37.2 percent from beyond the arc, but attempted just 6.8 shots per game and did not assert himself on offense.
When Rajon Rondo tore his ACL, Lee's numbers were expected to spike, but that was not the case as he battled with Jordan Crawford, Jason Terry and Avery Bradley for time in the backcourt.
To make matters worse, Lee was downright abysmal in the playoffs. He was benched for two entire games, played four minutes in a pair of others and for the series averaged 1.5 points on 20 percent shooting in 9.8 minutes per game. For a player earning $5 million per year, it's pretty hard to be more disappointing than that.
The central problem for Lee was that, despite having been a quality three-and-D player all his career, he simply could not grasp Boston's defensive system in his first season under Doc Rivers. He played solid one-on-one defense, but did not excel at the overall team aspect of the C's vaunted defense.
He also was forced to play outside of his comfort zone as a ball-handler with Rondo out, a move Rivers hopefully decides he is done experimenting with before the 2013-14 season.
What made Lee's year so disappointing is that he has always been a reliable double-digit scorer and an effective overall player who probably has the most complete game of any of the Celtics besides Rondo.
With Terry, Bradley, Crawford and Rondo all slated to be back in green Lee will again be fighting for minutes, but with Pierce and KG potentially gone he is going to need to work harder to fit into the team's system and hunt for his shots more.
Brandon Bass exceeded expectations in his first season with Boston, averaging 12.5 points and 6.2 rebounds while emerging as the team's starting power forward, but there was clearly a slight regression in his first season since signing a three-year, $19.4 million deal with the C's.
Bass improved as the 2012-13 season went on, but wound up averaging 8.7 points, 5.2 rebounds and one assist while shooting 48.6 percent from the field. He played four less minutes per game and averaged less free-throw attempts than in the 2011-12 campaign.
Early in the year he found himself losing minutes to rookie big man Jared Sullinger and simply struggled to connect from the field. Because Bass' offense is primarily as a pick-and-pop big man, it can be tough to leave him out on the floor when he is misfiring on his jumpers.
When Sullinger's back injury proved season-ending, Bass elevated his play, averaging 13.9 points on 57.3 percent shooting in April. His postseason numbers of 6.7 points, 6.7 rebounds and 1.2 assists might not seem all that impressive, but they only tell part of the story.
Though he did not look for his shot much, he posted two 10-rebound games and scored 17 points on seven shots in the Celtics' Game 5 win at Madison Square Garden.
With the future of KG in Boston so uncertain and Sullinger's back a serious concern, Bass is currently the only true power forward on the roster capable of logging 30-plus minutes per game. While the front office will likely bolster the depth either through free agency, trade or the draft, the team needs Bass to play like he did in his debut season in green.
No one expects Brandon Bass to morph into a nightly 20-10 threat, but he needs to be a more consistent presence offensively instead of disappearing at times and use his strength inside to make a bigger impact on the glass.
He should be the starter yet again for the 2013-14 season, but if he wants to see heavy minutes he needs to rediscover his offensive game.
Avery Bradley first emerged for Boston when Rondo was banged-up during the 2011-12 season, and there was hope that when he stepped into the starting point guard role with Rondo out this past year that he would again manage to find another gear.
That didn't happen, but Bradley did manage to make the All-Defensive Second Team while averaging 9.2 points, 2.2 rebounds, 2.1 assists and 1.3 steals per game. He shot the ball poorly—40.2 percent overall and 31.7 percent from beyond the arc—but Bradley has never been renowned as a perimeter marksman and was coming off of double shoulder surgery to boot.
On the surface, Bradley's numbers are perfectly adequate, but his PER of 8.89 was absolutely horrid. Granted, in 2011-12 it was just 11.31, nestling him snugly between Mike Miller (11.4) and Omri Casspi (11.26), but that also factors in the beginning of the season when he was barely used.
Bradley's defense was as solid as ever in the regular season; he continued to be a pest full-court and a tenacious defender on both guard positions, but could not keep that up in the playoffs. He was handled comfortably by Raymond Felton, who drove past him to the rack with ease during the six-game series.
His offensive game regressed, as he was erratic from the three-point line and not nearly as consistent from the corners as he was in 2011-12. Bradley is a good mid-range shooter and cutter, but he needs to add more to his repertoire and become a consistent double-digit scorer going forward.
Bradley also needs to work on his ball-handling and facilitating. Though he is not a true point guard and will log much more time at the 2-guard spot. Bradley never notched more than five assists in a game, and he hit that mark just twice during the regular season.
He's obviously never going to be the kind of passing wizard Rondo is, but with Pierce's days in Boston numbered the team could use a secondary playmaker in the backcourt capable of running the offense for small stretches of time. Since neither Lee or Terry are going to be that guy, the pressure falls on the shoulders of the 22-year-old Bradley.
In the playoffs, Bradley's numbers dropped to 6.7 points, 2.2 boards and 1.3 assists on 40.5 percent shooting and 25 percent from behind the three-point line. He had an excellent Game 6 (15 points, four assists and three steals), but was a non-factor offensively in the rest of the series and did little play-initiating.
The Rondo-Bradley backcourt is still projected to be the future in Boston, and having Rondo back all take a lot of pressure off Bradley as a passer, but he needs to improve as a shooter and a decision maker. If Bradley can add a more consistent three-pointer and became a better finisher at the rim, he has the potential to be one of the league's few elite shooting guards.
Doc Rivers has never been a coach to put much faith in rookies, but the talent and basketball IQ of Jared Sullinger, the 21st overall pick in 2012, made it impossible for Rivers to make him ride the pine.
The inclusion of Sully on this list is by no means a critique of his play in the same manner as the other players here, it's the opposite, actually. Before he went down, Sullinger was one of the few bright spots Boston had in an otherwise bleak 2012-13 season, and he looks like a potential future building block if he can stay healthy.
In 45 games before his season-ending back injury, he averaged six points, 5.9 rebounds and 0.8 assists on 49.3 percent shooting and made major strides as the campaign went on.
During the month of January, prior to his injury, Sullinger was averaging seven points and 7.2 rebounds on 49.5 percent shooting in 23.2 minutes while stealing playing time from Brandon Bass.
Which current Celtic must step up the most?
Whether Garnett is back in Boston, these Celtics need Sullinger for his ability to control the glass on both ends of the court. He is by no means a high-flyer, quite the opposite, but he is excellent at carving out position and using his body and length to beat taller players on the boards.
He is also strong enough to play some minutes at center despite his lack of height, a very valuable skill on this size-strapped squad.
During the regular season he demonstrated an improved mid-range jump shot and an emerging set of post moves, both of which he must continue to hone in the offseason.
Health is the biggest question mark for Sullinger, because with his level of talent and his high ceiling, there is no reason he can't emerge as one of Boston's franchise pillars in a year or two. Remember, this is a player who could have been the top overall pick if he had declared in 2011.