BOSTON - It may be hard to remember a recent Celtics scene with more sheer optimism. Kevin Garnett, fresh in from the Twin Cities in the middle of the table, a broad smile, flanked by a beaming Paul Pierce and Ray Allen.

No, they're not the new Big Three yet; Boston general manager Danny Ainge made that clear Tuesday. They haven't won anything.

But the addition of the 6-foot-11 Garnett has shaken the foundation of the Eastern Conference and awoken a somnolent Celtic nation like a 7.5 Richter scale earthquake. Sportsbook.com has put Boston as a 5-2 favorite to win the East and gulp -- 5-1 -- to win the 2008 NBA title, trailing only the Mavericks, Suns, and Spurs.

"From low expectations to high expectations, that's what we want," Celtics coach Doc Rivers said.

Or, as Pierce noted, "I asked for veterans. I didn't expect to get a 12-time All-Star."

Hey, he's only been to 10 All-Star games, but who's counting?

Garnett made his first appearance as a Celtics player Tuesday, capping a whirlwind 72 hours he described as "like being in a Lamborghini driving 200 with your head stuck out of the window." He passed his physical and signed a three-year extension (for roughly $60 million) to the two years he had left on his contract.

Getting Garnett was a monumental coup for Ainge and the Celtics, as was the go-get-'em attitude by ownership, which now will have to deal with the dreaded luxury tax down the road. So what? This is Kevin Garnett.

"This was an opportunity that came along," said Robert Epstein, one of the team's owners. "How do you let something like this go by?"

They couldn't. They didn't. They had Garnett in their grasp a month ago, but the situation wasn't right. But after the draft-night addition of Ray Allen, and with the rather transparent rebuilding effort about to happen in Minnesota, Garnett started to think about moving for the first time in his career.

"Initially, I had no interest leaving Minnesota," he said. "But after talking with [owner] Glen Taylor, his vision of the future was very different from mine. And when Boston [traded for] Ray Allen, the whole thing changed for me. I could see myself in a Celtics jersey. ... I got to thinking this may be the best opportunity for me to win a ring. So, here we are."

Ainge and Rivers did the appropriate keening for the losses of the players dealt, Al Jefferson in particular. But even though the Celtics surrendered five players and two draft picks, they looked and felt like the winners Tuesday.

Pierce said he was so excited that he felt like a rookie again.

"A big load has been taken off my back," he said.

Garnett and Allen are only too willing to take some of that load off of Pierce's back -- and take the Celtics where they haven't been in two decades.

"We still have things to prove," Garnett cautioned. "But I will say this: We'll be a force to be reckoned with."

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