A little more than a quarter into the NBA season, a handful of really good storylines have emerged. Last year’s runners-up, the Detroit Pistons, have managed to improve after the very public departure of head coach Larry Brown. There’s a new king of basketball in L.A., the Clippers, though the Lakers aren’t giving up their crown easily. And Phoenix, the team with the best record in the league last season, continues to impress this season despite the absence of its best player, Amare Stoudemire.

Yet amid all these intriguing developments, the San Antonio Spurs, winners of two of the last three NBA championships, are right on target to repeat. This isn’t news per se, but it’s surprising given the amount of time and energy the league devotes to burnishing its image that the Spurs, who play the Knicks tomorrow night (and yeah, we’ve reached one of those ugly junctures where the best reason to watch the Knicks is to see their opponents play), have been allowed to fly under the radar.

The Spurs are a multinational collection of talents who play a highly integrated brand of team ball highlighted by ferocious defense and resourceful offense. Yet outside of South Texas, they have gone largely unnoticed. You’d figure some team might try to emulate the Spurs. After all, their roster construction and overall gameplan have led to a couple of rings and perennial contention. They win because they almost always field one of the league’s top defensive teams. Their gameplan is built around shot blocking in the paint, and while All-Star fixture Tim Duncan excels at it, players without a history of rampant fly swatting like Nazr Mohammed and Robert Horry have acquired the skill after arriving in San Antonio.

The Spurs’ perimeter defense excels at closing out on 3-point shooters, and swingman Bruce Bowen can neutralize most star guards and small forwards. When they lose, it’s usually because their opponent shot unusually well.

Unlike the Knicks, who often scramble to put five capable bodies on the floor, the Spurs allocate playing time based on defense intensity. Glenn Robinson spent 10 years acquiring a reputation for lazy defense, but when he joined the Spurs last spring, he shocked observers with his energetic contesting of opponents’ shots. Those who don’t D-up find themselves glued to the end of the bench.

Coach Greg Popovich and team President R.C. Buford recognized that San Antonio were almost an opponent’s blown defensive assignment (Rasheed Wallace of Detroit made the bizarre decision to leave sharpshooter Horry open at the end of Game 5 and Horry canned the game-winner) from losing in last year’s finals, so they aggressively fortified the offense this past off-season. During the summer, they brought veteran guards Nick Van Exel and Michael Finley and Argentine big man Fabricio Oberto into the fold.

However, it isn’t the new additions, but guard Tony Parker who is supplying a big boost to the offense. The Belgianborn/French-reared point guard is shooting an eye-popping 54.4% from the field this season. He still can’t hit from behind the arc, but he’s also smart enough to know it, and has stopped shooting from out there; Parker has attempted only 12 treys all season (Knick fans probably wish Stephon Mabury, at 21.9% from downtown, would show similar restraint).

Parker is averaging 20.1 points, assists, and four rebounds a game. He would be a good candidate for the league’s Most Improved Player except that he was already an All-Star caliber guard.

Parker’s stellar play has obscured the struggles of the newcomers to fit into Popovich’s system. Although Finley has enjoyed a couple of big games, his 41.6% shooting illustrates why the Mavericks decided to cut ties with him. Van Exel is even worse, hitting only 40%, and Oberto has yet to earn much floor time. Add to this another down season from Barry, and you have a defending champion that is largely dependent on the starters, and in particular on their stars.

As long as the Spurs stay healthy, this won’t make much of a difference in the playoffs, as every team plays relies heavily on their starters, but during the grind of the regular season, it means those rosy forecasts for 65, even 70 wins will need to be scaled back to something more like 55-60 wins and a trench battle with Dallas for the Southwest Division crown. However, without a historic chase to elevate their profile, it probably means San Antonio will likely continue to fly under the radar all the way to the NBA Finals again.

Parker, plus fellow likely All-Stars, Duncan and Manu Ginobili will pose the biggest threats to the Knicks tomorrow night. The Knicks have played such porous defense lately that it’s hard to imagine anyone making a difference. In six straight losses, the New Yorkers have allowed more than 100 points per game.

When the Knicks have the ball, however, it will be interesting to see how rookie power forward Channing Frye does in his matchup against Duncan. Frye, averaging 14.8 points and 6.5 rebounds in 27.9 minutes a game, has shown a surprisingly solid game, but Duncan is only one of the most fundamentally sound players in NBA history. The local’s best hope is that the Spurs are weary from playing their second game in as many nights.

mjohnson@nysun.com