Well that was a fun one, huh? Amazing how one solid win will change the tone in the media and blogosphere, too. Everyone who said the season was over two days ago is now fixing for a big deadline acquisition. How it goes, I guess.

I never doubted that the Mets’ lineup would eventually hit — and I’m not willing to take one game as evidence that they continue doing so — so I’m more interested in Jon Niese’s performance last night.

Niese didn’t have his best stuff, pretty clearly. He only struck out one batter, allowed seven hits over six innings, and pitched in traffic for much of his outing. But he induced a lot of weak contact, got groundouts when he needed them and worked past some shoddy defense behind him. I haven’t consulted pitchFX to back this up, but it seems like he has thrown his big, slow curveball more often and more consistently in his last few starts than he had been earlier in the season, (when he almost entirely abandoned it).

It’s good. Fans talk constantly about the Mets’ need for a “true No. 2,” whatever that means, and here’s Niese, at 23, pitching like at least that. Using ERA+ for a quick and dirty study, Niese has been the 22nd best pitcher in the National League in 2010, and only four teams have two pitchers who have been better than Niese.

That’s meaningless, of course. The goal is to have as many good starters as possible and not to label them one thing or another, plus ERA+ is not necessarily a good indicator of how a pitcher will perform moving forward. I’m just saying if you think the Mets don’t currently have a “true No. 2” guy, you’re wrong. Plus, with the emergence of R.A. Dickey, Niese has arguably been only the Mets’ third-best starter.

I keep getting bogged down in things that don’t matter. What does matter is that Niese is 23, under team control for the foreseeable future, and appears to be pretty damn good. Granted, 107 2/3 — or 147 1/3, if you count the last two seasons — Major League innings are not an indicator of much. Plenty of pitchers have started better and fallen apart. But Niese’s Major League numbers in his first full season are in keeping with his Minor League history, so there’s reason to believe he’s actually this good.

And that’s exciting. I’ve been waiting so eagerly for so long for the Mets to have a solid crop of young, cost-controlled players to help them create a sustainable winner, and it appears they finally might. The jury is still out on all of them — Niese and Ike Davis included, and certainly less-proven guys like Josh Thole and Ruben Tejada and all them still in Double- and Triple-A. Some will fail and disappoint us. One or two might be better than we hoped.

I generally try not to link back to things I’ve written in the past because I’ve been wrong about too much, but here’s what I wrote in September:

Eventually, trading away too many Minor Leaguers leaves a team short on Major Leaguers. Not Major League stars, just Major League guys. So the Mets overspend on free agents or trade more young players simply to fill their big-league needs. That not only costs them money they could be spending on the more deserving free agents, it costs them depth.

So every offseason, the Mets construct an elegant sand castle, only to have it destroyed by the first wave of trouble, whether it comes in the form of prolonged slumps or bad bullpens or injuries. In 2009, they were hit with a tidal wave, one no team could weather. But let’s not forget that the Mets weren’t exactly dominating before the injuries to Beltran, Wright and Santana.

Allowing young players to develop — even the ones who might not appear to be anything special — can provide sustainability. The Mets have a series of intriguing prospects of various repute, including recent callup Josh Thole as well as Fernando Martinez, Ike Davis, Ruben Tejada, Reese Havens, Jonathon Niese, Brad Holt and Jenrry Mejia.

None of these players, with the possible exception of the injured Niese, appears ready to help the Mets by Opening Day 2010. But all of them could potentially help by 2011. With a year of development time, the Mets would have a better sense of what to expect from their prospects and a sharper idea of which of their numerous holes need to be filled by players from outside the organization.

Whether design or by accident, the Mets followed that plan. They kept the farm system intact in the offseason. And now, I think and I hope, we’re beginning to see the next winning Mets team take shape. I just hope they don’t screw it up.