BOSTON -- Kevin Garnett wasn't afraid to come out afterward and state exactly what this game was: a measuring stick.
"That is an elite team," Billups said.
Elite, maybe, but not elite enough to measure up to the franchise that has been the class of the Eastern Conference for the better part of the decade.
Elite, maybe, but not smart enough to avoid a boneheaded play at the end.
Elite, maybe, but not wise enough to get the ball into the hands of Ray Allen or Garnett, the two guys who had been putting their heart and soul into every second of this playoff-like game, instead of giving it to Paul Pierce on their final possession, entrusting the biggest shot of the game to a player who had been looking tentative all night.
There are at least a dozen different reasons why the Detroit Pistons were able to eke out an 87-85 victory over Boston on Wednesday night in what was easily one of the most competitive, riveting and intense games we've ever seen played in mid-December, but all those reasons begin to boil down to the same common denominators: experience, savvy and depth.
When did the Pistons begin to seize control of the game? Not until the early part of the fourth quarter when Celtics coach Doc Rivers gave Rajon Rondo a rest and handed over the ballhandling chores to Eddie House, who could barely get the ball over the halfcourt line against the suffocating defense of Lindsey Hunter, still regarded as perhaps the top on-the-ball defender in the league. A 9-2 run put the Pistons ahead 70-67 before Rondo returned, and Detroit never trailed again.
When did the Pistons deliver the knockout punch? Well, the play-by-play and the replays will tell you it came when Billups faked Tony Allen off his feet and drew a foul with 0.1 seconds left that sent him to the line for the tiebreaking and game-deciding free throws. But a big assist came moments earlier when the Pistons were exiting their timeout and Tayshaun Prince noticed that Tony Allen had checked back in as a defender.
"Tay told Chauncey to give Tony Allen a pump fake because Tony was just coming in off the bench cold," Pistons coach Flip Saunders said.
Billups confirmed the story, saying Prince gave the same message to Richard Hamilton knowing that one of the two was going to end up with the ball in his hands for the final shot.
"Anybody could have went for that [fake]," Garnett said afterward, cautioning everyone not to single out Tony Allen for blame. "This was a good game for us to learn from and dissect. We wanted to measure where we were, and like Paul said, I'd rather deal with [a loss] now than later. No one said this was going to be easy, and we just have to go through this type of process and learn from it."
The loss was only the third of the season (and the first at home) for the Celtics, who will continue to measure themselves over the rest of this month as they play Chicago and then Orlando before embarking on a four-games-in-five-nights West Coast trip to close out December. They'll have a 29-game body of evidence to sort through by the time January rolls around, and we'll all have a better measure of whether this Celtics team is truly as elite as Billups was calling them, or whether they're merely a very good team with some very real flaws that'll need to be addressed before the playoffs come around.
"No one's going to remember this game next week," Saunders said. "The statement right now is you have two teams that are pretty evenly matched."
We'll go ahead and partially agree with Saunders' opinion that no one is going to remember this game a week from now, but we'll qualify that agreement by limiting it to the Pistons. They will find it easy to put this one in their rearview mirror, but the same cannot be automatically said for the Celtics.
This game will stick with them because this game humbled them, and truth be told, they were a team in need of some humility after breaking out of the gate with a 20-2 record that was among the greatest starts in NBA history.
Pierce was kicking himself afterward for not letting a little more time come of the clock before he attempted his 15-foot fadeaway from the corner that everyone in the arena could tell was going to be two feet short from the moment it left his hand. Tony Allen was beating himself up for falling for Billups' pump fake, and Rivers was no doubt second-guessing his own late-game substitutions when he turned first to House and then to Tony Allen instead of going with his starter Rondo, who had played one of the better games of his career (14 points on 7-for-10 shooting with seven assists and three steals).
The Celtics will get another chance Jan. 6 to measure themselves against the Pistons, only next time it'll be on Detroit's home court. And since it is still very, very early in a long, long season, the Celtics' hurt from this loss will have faded by then. But what the Celtics will hang on to is their memories of how electric the building felt, how intense the game was played and how close they already are to being equals with the Pistons.
"I think losing games levels you out. As much as you don't like it, it always humbles you and makes you put in that hard work," Ray Allen said.
The Celtics are very good, but this loss might be exactly the thing they needed to get a better understanding of where they stand. Because even though they stand alone atop the overall NBA standings, no one can rightfully say -- especially after this loss -- that the Celtics are the class of the league. They may be by the time mid-June rolls around, but they aren't yet. And in order for them to make it to mid-June, they're eventually going to have to get past a Pistons team that they couldn't quite measure up to in mid-December.
Chris Sheridan covers the NBA for ESPN Insider. To e-mail Chris, click here.