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Jeff Green was the standout of Boston's exhibition slate.BOSTON -- The Boston Celtics closed out their eight-game exhibition slate Sunday night with an 88-79 loss to the Philadelphia 76ers at TD Garden. Boston now has eight days to prepare for the 2012-13 season opener in Miami. But before we look ahead, let’s run down what we learned from Boston’s preseason tilts:

* GREEN MACHINE: Pundits spent the offseason squabbling about whether Jeff Green deserved the four-year, $36 million contract he inked after sitting out all of last season while recovering from surgery to repair an aortic aneurysm. Green didn’t just show he’s healthy enough to be a real contributor this season, he might have been Boston’s best player in the preseason. Don't take our word for it, ask his coach.

"Jeff stood out, probably more than everybody," Doc Rivers said. "I thought he established himself with everybody, which I thought was very important for him. We can tell them how good he is; he had to show them. And I thought he did that."

Green capped his postseason by chipping in a double-double with 12 points and 10 rebounds while operating as a starter Sunday night against the 76ers. His athleticism dominated Boston's preseason highlight reel, from strong drives to the bucket for poster dunks (sorry, Jason Kidd) and crazy chase-down blocks (sorry, Mychal Thompson), the 26-year-old Green brought something this Celtics team has desperately lacked in recent seasons.

His teammates downright gushed about his newfound aggressiveness.

"Jeff's a lot more aggressive than I can remember, man," Kevin Garnett said. "I can remember when he first got here [at the trade deadline in 2011], maybe he was just understanding his role or whatever, at times he was tentative. Now I think he has a different appreciation; he's playing like it. He's playing like he knows he's going to be here, he understands his role, he's aggressive, and we're going to need that from him. I told him he has an old-school game, like James Worthy, and to see him back, see him refreshed, doing the things he loves to do, it's good to see him back, so I'm happy for him."

Informed that Rivers' crowned him as the fictional preseason MVP, Green said, "I doubt that. He's lying to you all. I think he was being nice to say that. I'm very hard on myself. I felt I could have done a lot more. I thought I could have been better on defense, as far as team-wise. I think I had some lapses during the preseason, but this was a good start to my comeback, my whole journey back playing again. So I'm grateful for everything that's happened this preseason, but I'm never content with what I did. I still have some room for improvement."

* OPTION OFFENSE: Rivers spent the preseason mixing and matching his talent like a mad scientist. He utilized seven different starting lineups over eight games, including trotting out a starting five on Sunday that essentially featured three power forwards (Green, Garnett and Brandon Bass). Rivers wouldn't tip his hand on lineups, but admitted there likely will be multiple variations of his starting unit and he'll allow on-court production to dictate what lineups get used more than others.

"We know what we like," Rivers said. "I think it's pretty simple to figure out your starting lineup. I do think this is going to be an unusual team in that I don't think we'll have a staring lineup for most of the year. I think we may move that one guy around a lot."

Rivers will keep his Big Three -- Garnett, Rajon Rondo and Paul Pierce -- together, but can pick the other pieces with the goal of matching up (or exploiting) an opponent. That could mean Bass and Courtney Lee on one night, or Green and Jason Terry the next. A healthy Darko Milicic could draw occasional starts and move Garnett to power forward in order to limit wear and tear early in the season, or rookie Jared Sullinger proved he was ready for a potential starting role if the Celtics want to utilize Bass with the reserves.

* DEFENSE STILL A WORK IN PROGRESS: For all the excitement about the potential for increased offensive production with Boston's new weapons, the Celtics suffered through some head-scratching struggles on defense this preseason. Rivers chalked up some of those woes to new personnel, but admitted the team needs to make strides.

"I don’t want us to think we’re just going to outscore teams," Rivers said. "But if we can stop teams, with what we have on offense, I think we can be really good."

Later he added, "I think we still have to be a better defensive team, consistently, to be a great team."

* EYE ON THE INJURY BUG: The biggest obstacle to Boston’s success in recent seasons seemingly has been health. The Celtics spent their offseason adding depth at every position, but navigated the preseason without Chris Wilcox (back) and Avery Bradley (shoulders), while Milicic (wrist), Pierce (ankle) and Bass (knee) all got dinged up along the way.

On the positive side, Boston emerges from camp in good shape (Pierce and Bass played Sunday, while Rivers said Milicic was held out simply as a precaution). If the Celtics can avoid hurting each other this week in practice, they'll enter the regular season in quality shape (with Wilcox and Bradley expected to add a boost down the road).

Maybe that's why Garnett was quick to bring up health when asked if he was happy with how camp played out for Boston: "Obviously, we didn't have any serious injuries or anything like that." The Celtics would prefer to keep it that way.

* JOSEPH WINS THE CAMP BATTLE: With a strong showing over the final three games of the exhibition season, rookie second-round draft pick Kris Joseph appears to have nailed down his roster spot. Considering he was on a completely non-guaranteed deal entering camp, that's no small feat. Joseph outlasted guards Dionte Christmas and Jamar Smith, both of whom had partially guaranteed contracts (and were set free before the team inked Leandro Barbosa to add depth at the guard spot). Joseph isn't necessarily out of the woods -- his contract won't be guaranteed for the season until early January. But he showed potential late in the exhibition slate and will stick around for his efforts.

Said Rivers: "I thought Kris Joseph really helped himself. I thought he played terrific. And we put him in terrible positions. We put him on the floor where him and [6-foot-7 camp invite] Micah [Downs] were the point guards. I mean, that's not fair to anybody. But he did other things. He's a terrific offensive rebounder at his position. So you like that in him."