Yesterday I cautioned that while it’s still early, we shouldn’t overreact. But Dallas Mavericks guard Greg Buckner begs to differ.

“We can’t keep saying, ‘It’s still early,'” he said after his team fell to 0–3 with a home loss to lowly Golden State, “and lose six more.”

Indeed, the Mavericks’ early-season woes are troubling. Last year’s finalists are winless, and two of the losses came on their home court. On its own, each of the defeats merits little more than a shrug. But taken together, they are a worrying sign for the defending conference champs. Including last year’s Finals, the Mavericks have now dropped seven straight games.

It could get worse, too. Forward Josh Howard sprained his ankle in the loss to the Warriors and isn’t likely to return soon. Guard Jason Terry clotheslined Golden State guard Monta Ellis and is likely to face suspension — which could run multiple games when one considers Terry isn’t a first-time offender (remember that stomach punch on Michael Finley in last year’s playoffs?).

Other than Dirk Nowitzki, those are the Mavs’ top two scorers — in fact, the two are the only ones averaging more than eight points a game in the early going. So Dirk probably will be going solo as the Mavs face tough road games against the Clippers and Suns this week; 0–5, anyone?

That explains the “what,” but let’s talk about the “why.” A big reason for the slow start is that one of Dallas’s biggest advantages — its bench — has been a liability these past three games. Devin Harris, Jerry Stackhouse, Austin Croshere, and Greg Buckner have all hit 37.5% or less; Anthony Johnson and Erick Dampier are hitting at a better clip but have taken the fewest shots of the bunch. Additionally, the Mavs continue to call a maddening number of plays for Stackhouse despite his fairly low efficiency; he’s fourth on the team in fieldgoal attempts but shooting 33.3%.

Perhaps more telling than the shooting percentages are the free-throw rates. A year ago Dallas averaged .364 free throws per field-goal attempt, one of the top figures in the league. So far this year they’re at .237, which is pathetic. Stackhouse, Harris, and Terry are the biggest culprits, but nearly everybody on the roster has a lower free-throw rate than a year ago.

I point out that change because it indicates a larger, roster-wide concern: age. The Mavs made a concerted effort to import veteran players over the summer, feeling their team lacked the experience and toughness to put away the Heat in last year’s Finals. However, they might have gone a little overboard.

By exiling young talents like Marquis Daniels and importing the likes of Johnson and Croshere, the Mavs now have five key players on the wrong side of 30. Terry is 29 and Nowitzki 28; while that doesn’t make them graybeards, it’s hard to argue they’ll be any better than a year ago. And taken as a whole, it’s possible the change made the team substantially slower than a year ago. One way that tends to manifest itself, statistically, is in a low free-throw rate, which is exactly what the Mavs have. It’s only three games, but the drop from a year ago is jarring.

That’s not to dismiss the value of having guys who have been there before; it sure seemed the Mavs as a group could have dealt better with the Finals press circus than they did. But the first step remains getting there, and that requires a talent level equal to that of the other elite teams. In acquiring the requisite experience, the Mavs may have unwittingly left themselves short on skill and athleticism.

The Mavs’ archrivals in San Antonio could have told them all about how this strategy works, because the Spurs took the same path a year ago. They were defending champs at the time, and brought in Michael Finley and NickVan Exel in the hopes of repeating. But they found out what Dallas may learn this year: Sometimes those guys’ pasts are a lot better than their present. Finley was passable, but Van Exel absolutely killed them in the playoffs.

So this year, the Spurs wisely went in the opposite direction. They traded veteran center Rasho Nesterovic to Toronto for Matt Bonner, and allowed big man Nazr Mohammed to depart as a free agent along with Van Exel.

Instead of signing veteran retreads to take their spots, the Spurs promoted from within. A third-year pro, Beno Udrih, was allowed to reclaim the backup point guard job, one he handled perfectly well as a rookie before it was unnecessarily handed to Van Exel a year ago. The center job is a committee headed by Fabricio Oberto, who languished on the bench last season behind the two now departed vets. San Antonio went even younger behind him by nabbing Jackie Butler from the Knicks, a longterm move that could pay big dividends in the second half of the season.

The results were pretty clear at Madison Square Garden on Monday, as the Spurs’ young legs helped carry them to the win on a night when Tim Duncan was relatively quiet. Udrih scored eight points with nary a turnover in 16 productive minutes off the bench, helping to stem the tide when the Knicks’ second unit got hot. And with veteran Robert Horry looking wobbly on his 36-year-old legs in the first few games, Bonner got the call and chipped in five points off the bench. Meanwhile, the Spurs’ new tag-team center combo of Oberto and Francisco Elson did a serviceable job on Eddy Curry (13 points, five turnovers) and controlled the boards (10 between them).

So if Dallas’s struggles continue (and Miami’s for that matter), you can score it as yet another cautionary tale of overvaluing experience. It has value, of course, but that has to be offset by two realities: First, that the name of the game is putting a ball in the basket more times than the other team, and second, that young men invariably are better at this than old ones.

jhollinger@nysun.com