It's all about windows in Beantown these days.

Four years removed from the franchise's last NBA title, the clock is ticking on this version of the Celtics. Kevin Garnett, Ray Allen and Paul Pierce are all on the downsides of brilliant careers and the front office has seemingly soured on its one ascending star, Rajon Rondo.

Concerned with reported "maturity" issues, the C's shopped Rondo before training camp in the hopes of luring Chris Paul to town, a move that was stillborn when the All-Star, who eventually landed in LA with the Clippers, made it clear he had no intentions of signing a long-term extension with the Celtics.

Boston's concerns with Rondo were elevated after an incident between Games 2 and 3 against Miami in the playoffs last spring. According to multiple sources, Rondo's errors were being discussed in a team meeting when he lost it, criticizing teammates before throwing a bottle that shattered a video screen.

Those kinds of temperament concerns have hounded Rondo since his days at Kentucky and have convinced the Celtics he can not lead, not exactly a comforting thought to have about your point guard, even one as talented as Rondo.

Problems aside, the Celtics certainly have enough talent to dominate a slowly improving Atlantic Division but a condensed 66-game schedule is not going to do the legs of aging players any favors.

Doc Rivers' ability to navigate the regular season and keep his veterans fresh for one last run will be the key in helping Boston keep its "window" ajar for one more season.

2010-11 Results: 56-26, first in Atlantic; lost to Miami in East semifinals.

ADDITIONS: PF/C Brandon Bass, G Keyon Dooling, PF Chris Wilcox, PF JaJuan Johnson, G E'Twaun Moore


PG- Rajon Rondo SG- Ray Allen SF- Paul Pierce PF- Kevin Garnett C- Jermaine O'Neal

KEY RESERVES: F Jeff Green, F Brandon Bass, G Marquis Daniels, G Keyon Dooling, G Avery Bradley

FRONTCOURT: Garnett, the NBA's resident bully, is one of the best power forwards of all-time and remains an incredibly unselfish teammate. That said, he's clearly on the downside of a spectacular career and Rivers will have to spell the "The Big Ticket" early and perhaps often to keep his balky knees healthy for a playoff run. Garnett is still an efficient player and has enough left in his bag of tricks to make things difficult for any opponent.

Pierce remains the Celtics' closer and is one of the NBA's best pure finishers. The 2008 NBA Finals MVP possesses a high basketball IQ, incredible savvy on the floor and the type of body control you simply can't teach. Pierce is also a very underrated defender.

With Shaquille O'Neal retired, Jermaine O'Neal is the only legitimate center left on the roster. A former All-Star, O'Neal has little left but Rivers will need 20 minutes or so from the big man and will have to mix and match minutes in the pivot, often going undersized with underrated ex-Magic forward Brandon Bass.

BACKCOURT: The "Boston Three Party" really became a fabulous foursome a few years ago when Rondo developed. For better or worse it's Rondo that is now the straw that stirs the drink in "The Town" these days. One of the game's quickest quarterbacks, Rondo is a triple-double threat despite lacking a top- tier, consistent jumper. He's also extremely tough and his ability to get on the boards really shows up against most guards. The book on Rondo remains simple, sag off him and make him take that suspect jumper. It also remains to be seen how he handles the fact that Celtics president of basketball operations Danny Ainge was shopping him so publicly.

Allen is still one of the finest pure shooters in the game and can come off the screen better than anyone since Reggie Miller. Ray-Ray has a lightning- quick trigger and is not afraid to take the big shot. In fact, Allen's marksmanship can take over any game when he heats up. Although aging, the UConn product is also an underrated defender.

BENCH: Rivers thought he would have a healthy mix of youth and experience on his bench but that was blown up when forward Jeff Green was diagnosed with an aortic aneurysm a week before the season was scheduled to start.

Green never fit in after being acquired from Oklahoma City at the trade deadline last season for the well-liked Kendrick Perkins but big things were expected this time around. He is a big-time talent that could have helped both offensively and with his perimeter defense.

Now the former first round pick is set for surgery on Jan. 9 and will miss the entire season. The aneurysm -- which occurs when a section of the aorta weakens and expands, putting it at risk of rupturing -- was first detected during a physical earlier in December. Doctors recommended surgery after Green underwent additional tests and the club has said the procedure "should completely repair" the condition.

"While we are saddened that Jeff will not be able to play this season, the most important thing is his health, and we were fortunate to have access to an amazing team of specialists to evaluate Jeff's case," said Ainge. "The entire Celtics family supports Jeff during this difficult time in his career."

Veterans Sasha Pavlovic and Marquis Daniels could get some of Green's minutes but are pale comparisons. Pavlovic can shoot the ball and gives energy on defense but offers little else while Daniels can produce in limited minutes but is too banged-up to be counted on consistently.

Keyon Dooling, an 11-year vet, can handle both guard positions but has been penciled in as Rondo's backup at the point. A wild card in the mix is second- year guard Avery Bradley. Ainge is really high on Bradley, the 19th overall pick in the 2010 draft, and thinks the youngster can offer much needed youth and athleticism.

"We just gotta give him a chance," said Ainge. "He needs game action. You gotta give him a chance to play. But, at the same time, just with his athleticism alone, and his energy defensively, he'll help us. He'll make mistakes, but he'll bring something to the table as well that we don't have."

Rookie JaJuan Johnson will also be eased into things. The 6-foot-10 Johnson was named the Big Ten Player of the Year and Big Ten Defensive Player of the Year after averaging 20.5 points, 8.6 rebounds and 2.3 blocks per game at Purdue in 2010-11.

COACHING: You can't help being impressed by Rivers when you are around him. The former point guard has done a wonderful job melding the egos of three superstars and managing personalities for the most part, perhaps the most important job of any NBA coach. Losing, a lead assistant for the second straight year (Tom Thibodeau and Lawrence Frank) is the kind of thing that will eventually start hurting, however. Meanwhile, Ainge threw a roadblock in front of Rivers with his handling of the Rondo situation.

OUTLOOK: The Celtics are still the class of the Atlantic but have clearly fallen a step behind both Miami and Chicago in the East. Health, stamina and chemistry will be the pressing issues for this experienced club in its quest for another title.

"I still think Boston is a team that could really benefit from having a short season because of the veteran status of their roster," NBA TV analyst Greg Anthony said. "The big advantage Boston is going to have is their core group of guys have gone through a lockout before. And I think Doc Rivers can do a really good job of resting his guys over the course of the regular season to prepare for the postseason."