It’s training camp, and normally that’s the time for sunny optimism and glass-half-full thinking about how this year can be better than the last one.

But in the case of the two local teams, it’s also where the happiness about each team’s recent change of direction runs into the grim reality that they’re each on the first mile of a long road of rebuilding.

Take the Knicks, for instance. Their fans are euphoric that Isiah Thomas has been deposed, and rightfully so: His reign of incompetence was one of the saddest chapters in the history of local sports. But the flip side of that excitement is that the damage from the Thomas era will take years to repair.

For a good reason why, just look at the Knicks’ roster. You’ll notice that while the names of the coach and team president are different, the players are almost exactly the same — Danillo Gallinari and Chris Duhon replaced Renaldo Balkman and Fred Jones, but otherwise it’s the same bunch of overpaid yahoos that got Thomas fired three months ago.

Even Stephon Marbury is still around, as owner James Dolan can’t quite swallow the idea of paying him $20 million to go away … even if this is a fraction of what he spent on last year’s dysfunctional mess. Jerome James is still around, too, believe it or not.

The other “must-go” Knick, Zach Randolph, is here as well, after the Knicks decided that the offers they received over the summer were too piddling to bother with. The hope is that he can put together a solid performance as a starting power forward and build up his trade value over the course of the season; as I’ve written before, there isn’t any urgency to trade him for another year to create cap space in 2010.

Randolph might also benefit from a likely lineup change. Reports are that Eddy Curry is looking poorly conditioned even by his own low standards, creating an opening for David Lee to take a starting spot in the frontcourt.

This makes all kinds of sense anyway, as Lee is much better suited to D’Antoni’s up-tempo style, makes a better frontcourt partner for Randolph because he doesn’t need touches on the block, and, most importantly, is just a better player. The fact that he didn’t start for the past two years owes more to Isiah’s desire to prove that his disastrous trade for Curry made sense than it owes to any advantage he held over Lee.

In the backcourt, Duhon joins the same gang of non-defending, shot-chucking star-wannabes that infested the roster a year ago. Jamal Crawford has been talked up as a Knick who could have a big year in D’Antoni’s system, but it takes more than a willingness to shoot to play well in this scheme. Nonetheless, he’ll likely start with Duhon in the backcourt with Nate Robinson as a sixth man.

The most interesting battle is at small forward. In a typically rosy training camp proclamation, D’Antoni said Jared Jeffries really surprised him in pre-camp workouts. I’m not sure if he was surprised by what a god-awful shooter Jeffries is, or whether the surprise was how such a mediocre player could get a five-year, $30 million deal. (D’Antoni, by the way, is nearly as glass-half-full as Thomas, so take all his preseason statements on matters such as these with an entire shaker of salt).

Quentin Richardson is in the mix, too, and might actually get in shape now that he’s reunited with the coach who helped him to a career year in Phoenix. But the guy to watch is Wilson Chandler — he played well down the stretch last year and is probably New York’s best hope of getting respectable production from the position.

Across the river, Nets fans are meanwhile left to contemplate their lack of a time machine. New Jersey has positioned itself to be in great shape by 2010; the unfortunate part of that strategy is that it’s only 2008.

The price for the Nets’ delay in nuking the Kidd-Carter-Jefferson nucleus is that they’ve left themselves with a much steeper rebuilding job. Trading Kidd for Harris and change a year ago was a nice start, but Jefferson had to be almost given away in order to unload his contract, and the Nets were pretty much strip-mined of other assets by the time they changed gears and started work on version 2.0.

Harris and Carter make a solid backcourt, at least, but perhaps not for long. There doesn’t seem to be a great deal of logic to keeping Carter around, since he’s due $48 million over the next three years and is at an age where his trade value will only diminish, so it makes sense for the Nets to take calls on him. But a deal may not come around until the trade deadline, when suitors are more desperate.

Until then, the important players to monitor will be the young big men. Yi Jianlian, Brook Lopez, Josh Boone, and Sean Williams aren’t much to look at in terms of past history, but this has the potential to be an excellent frontcourt a couple years down the road. Yi in particular has a serious upside as a quick 7-footer who can shoot, but he was terrible in the Olympics and has yet to put his skills together into a compelling package at either end.

The other key figure is Lawrence Frank, who will have to coach very differently from the way he has in the last few years. Instead of scratching and clawing for every win, he has to keep a longer-term perspective and allow the kids to work through their mistakes — something he was unwilling to do with Williams a year ago, for instance.

Regardless, it figures to be a long year for local basketball fans. The changes the Nets and Knicks made in the past year were important and long overdue, but it’s going to take a little time before they bear much fruit.

* * *

Six years ago, when someone called me at The New York Sun to ask if I would occasionally write about basketball for them, I had no idea it would turn into a regular gig for more than half a decade. In fact, my first reaction was, “Um, you know I don’t live in New York, right?”

It couldn’t have worked out better. The Sun’s analytical, contrarian bent to sports coverage fit me like a glove, and the editors and staff couldn’t possibly have been more pleasant to work with. That goes for the readers, too — I thank you all for taking the time, and even if I didn’t write you back I promise I read what you said.

This is our last paper, as you might have heard. But instead of mourning that fact, I prefer to look back fondly on the Sun’s six-year run, and the fact that it survived that long in an era when newspapers are dropping like flies. Hopefully the concept of a local sports section that is as heavy on analysis as it is on reporting will live on, even if this newspaper does not.

jhollinger@nysun.com