For NBA fans of every faith, there’s a special treat awaiting this Christmas: Detroit vs. San Antonio. Despite the networks’ baffling decision to make this the warm-up game for the tired, overhyped Shaq vs. Kobe melodrama, there is no doubt that the Spurs-Pistons showdown is the main event. The two clubs met in a hotly contested Finals a year ago and picked up right where they left off this fall, dominating the league thus far.

Through a quarter of the season, the two clubs appear light years ahead of the rest of their competition, to the point that boredom appears their chief enemy. Detroit, despite learning a new system under Flip Saunders, has raced out to a 20-3 start, while San Antonio has shrugged off a series of injuries to Manu Ginobili to post a 20-6 mark. The standings actually understate how much better than their rivals these two clubs are. They have the NBA’s two best records even though each has a played a leaguehigh 14 road games. Amazingly, Detroit has played fewer home games than any team in the league.

Unlike in previous seasons, the Spurs-Pistons matchup also presents a contrast in styles. As I’ve mentioned in this space several times before, the Tim Duncanera Spurs are perhaps the most dominant defensive team in NBA history. They’ve led the league in Defensive Efficiency – my measure of a team’s points allowed per 100 possessions – for three straight seasons. This year they’ve struggled by their lofty standards, as they only rank a close third behind Indiana and Phoenix at the moment. Of course, that ranking is unduly influenced by the 38 points the Spurs’ scrubs gave up to the Knicks in the fourth quarter on Wednesday, long after San Antonio’s starters had finished embarrassing New York on its home court.

But what makes this year’s matchup even more compelling than last year’s Finals is Detroit’s personality change under Saunders. For the past two seasons under Larry Brown, the Pistons played low-scoring scrums that were about as stimulating as your co-worker’s week-old fruitcake. In each season, Detroit’s Defensive Efficiency mark nearly rivaled that of San Antonio. Not surprisingly, that produced a low-scoring, defensive affair when the two met in the Finals, which didn’t exactly produce a TV ratings bonanza.

Under Saunders, however, the Pistons have done a complete Flip. Detroit is now the best offensive team in basketball, averaging a whopping 109.3 points per 100 possessions. By comparison, the league average is 101.8, and even a good offensive team like San Antonio averages just 103.8.There was absolutely no warning this was coming – in the previous two seasons, the Pistons finished in the middle of the pack offensively, and have the same starting five as a year ago. Yet guards Chauncey Billups and Richard Hamilton have thrived in the new offense, with each likely to make his first All-Star team.

Had the Pistons shown such a burst of offense and kept their defense at the same level it was through the Brown era, they’d be staring down the all-time record for wins in a season (it’s 72, by the way). But defensively, Detroit has slipped quite a bit. The Pistons’ 101.0 mark in Defensive Efficiency is just below the league average, and quite a bit behind San Antonio’s impressive 96.2 rating.

On paper, Detroit’s season still has been the more impressive of the two. The Pistons have five wins by at least 20 points and only once have they truly been hammered (Dallas whacked them 119-82 on November 19). But it’s quite possible that the defensive slump will prove short-lived. The Pistons’ top defender, Ben Wallace, has battled a series of nagging injuries that have limited his defensive effectiveness (witness that posterizing jam by the Knicks’ Trevor Ariza a few weeks ago), but if he returns to Defensive Player of the Year form, this team will be downright scary.

On the other hand, it’s hard not to be impressed with what San Antonio has done as well. Take the second-best player out of the equation for almost any team in the league and they’ll struggle mightily. Yet Ginobili has missed eight games and been a shadow of himself in several others due to a foot problem. But the team has kept right on rolling.

Moreover, this is a team that openly admits to pacing itself for the postseason. Veterans like Robert Horry and Nick Van Exel may as well have “Do not wake until April” written on their foreheads, while Ginobili is only playing 29 minutes a game to reduce the wear and tear his reckless style engenders.

That’s why I’m so excited for this game, however: It’s a rare regular season game that will be played like a playoff game. Both teams are aware of how high the stakes are. Remember that Game 7 in the Finals a year ago, and how the San Antonio crowd helped the Spurs rally in the fourth quarter? Don’t think for a minute that the outcome would have been the same had the game taken place in Detroit’s raucous Palace at Auburn Hills, where the teams will meet on Christmas.

The Game 7 host, of course, is the team with the best regular-season record. And with the Spurs already trailing the Pistons by three games in the loss column, they can ill afford to fall another game off the pace on Sunday. Don’t be surprised if Ginobili makes a miraculous recovery from his foot injury in time for the game, or if Horry and Van Exel suddenly seem a lot more motivated than they have at other times this season.

Meanwhile, there’s a revenge factor in play for the Pistons. Yes, they’re 20-3,but playing host to San Antonio in the teams’ first meeting of the new season has “statement game” written all over it. If the Pistons want to show that not even San Antonio’s mighty defense can keep their new and improved offense under wraps, Christmas Day would seem to be as good a time as any.

So sit down in front of the tube, grab a few eggnogs, and enjoy what promises to be a very entertaining matchup on Sunday. Because it’s not just a rematch of last year’s Finals – it’s also, in all likelihood, a preview of this year’s as well.

Mr. Hollinger is the author of the 2005-06 Pro Basketball Forecast. He can be reached at jhollinger@nysun.com.