Let’s assume that the Mets, after their annual thrashing at the hands of the Braves and with two games still left against the St. Louis Cardinals, now have no shot at the postseason. (I actually happen not to agree, but I’ll defer to the overwhelming opinion of the rest of the world for the sake of argument.) It’s at this point that we can start to look at what went wrong, and try to discern some lessons that the team should take into the off-season and next year.

The first lesson is that, left alone, this might not be a .500 team next year. Though not the most important reason the Mets had an excellent shot at the playoffs going into September, the solid play of veterans Cliff Floyd, Mike Piazza, Tom Glavine, and Roberto Hernandez was a big one. Even with his apparently season-ending injury, Piazza was as good with the bat as any National League catcher other than Chicago’s Michael Barrett, and Floyd has been one of the five best left fielders in the league; the pitchers, meanwhile, were better than any reasonable expectations.

What this means is that Mets fans can’t engage in the simple arithmetic of figuring that this 80-to-85-win team can win 90 or more next year just by filling the obvious holes on the right side of the infield and in the bullpen. To unseat the Braves, the Mets are not only going to have to improve in obviously weak areas, but to compensate for declines in areas that had been strengths this year, which aren’t limited to the veterans. David Wright, for instance, might again play at a near-MVP level next year, but you can’t count on that kind of production from a player his age.

The second lesson is that Willie Randolph needs some better relievers, not only because all managers could always use better players, but because it’s not clear he’s willing to run the Mets’ best pitchers out there with the season on the line. Various fiascos of late involving combinations of Braden Looper being left in games too long, being left in to face left-handed hitters he has no chance of getting out, Danny Graves being on the roster, Shingo Takatsu being given key assignments instead of Aaron Heilman, and the like have cast some really serious doubt on whether Randolph knows what he’s doing – even for a Randolph booster like me. There’s something to be said for going to veterans in the clutch, but young players are the main reason the Mets got as far as they did this year, and Randolph’s fine work in developing young players has to be matched by equally fine work in using them.

Along the same lines, it’s going to be pretty important next year that GM Omar Minaya not allow someone like Kazuhisa Ishii to be used inexplicably in place of someone like Jae Seo. There is a lot of promising pitching talent on the rise in the Mets’ farm system, and while it’s good to have reasonable veterans on hand, they can’t be allowed to stand in the way of younger, better players simply by virtue of their service time.

The last and most important lesson is that it’s star talent that drives winning teams. What’s the difference between this year’s Mets and those of the last few years? Essentially it’s Wright, Pedro Martinez, and a healthy Floyd. Even Carlos Beltran makes the point clear, because even at his worst,he’s still been an above-average player. A good team makes good decision regarding role players and young talent, but great teams have great players. It’s a rather obvious point, but one that sometimes gets lost in the fuss over crummy bullpen decisions and the like.

Because there are no great players on the free agent market this year, the Mets are going to be confronted with a choice. Should they fix the holes with decent players and hope that Wright and Martinez repeat their seasons while Beltran and Jose Reyes improve, making up for declines in other areas? Should they pick up an aging slugger like Manny Ramirez or Todd Helton in hopes of bringing a pennant to Flushing? The choice might be tougher than it looks; next year’s free-agent class is going to be, if anything, weaker than this one, with the likes of Aubrey Huff and Milton Bradley among the top prizes on the market.

Like many, I’ve been skeptical of the idea that the Mets need to get some $17 million star, but the truth is, it might be that or nothing. That leaves the Mets to ponder one difficult question: Is this team close enough to a pennant to really go for it? There’s no easy answer, but the rest of September will be telling.