What of the future? You do the math

But maybe it won't be so bad after all.

Barring some startling development - and with Danny Ainge as general manager it's wise to keep your mental seat belt fastened - the Celtics won't have to start contemplating that future for at least another year.

Still, there's been a glimpse of it during the first two rounds of the playoffs. The Celtics have been operating without Kevin Garnett, who is their best rebounder and defender, as well as their most reliable frontcourt scorer and passer. He is also universally acknowledged as the team's emotional and spiritual leader.

Without him, they aren't winning any championship; any reasonable person knows that. The same could be said about Paul Pierce or, despite his well-documented shooting woes in the Orlando series, which went to a Game 7 last night, Ray Allen. But it never just can be about winning a championship. Oh sure, the Celtics have been known to indulge in that silly rhetoric many times. Does the phrase "championship driven" ring a bell?

Talk is cheap. Star players often get caught up in declaring that they're only in it to win championships, and so forth. Well that's fine. Everyone needs a goal. Everyone starts out the season 0-0 with a dream of going 82-0 and eventually being on the last team standing.

The problem is that only one team wins, and everyone knows it. If you're on any of the teams that fall short, you can't spend too much time moping. The odds always were stacked against you in the first place.

Now if winning the championship is the ultimate satisfaction, it's not the only one. Being on a team that has a chance to win is pretty good, and it's more than most teams can say. Being on a team that can win 48, 50, or 55 games and which, given a break or two, could go deep into the playoffs, is a very worthy existence.

That was the only promise when the 2007-08 season began. Ainge had transformed them with his Seattle and Minnesota trades to obtain Allen and Garnett, and then bolstered his squad by signing James Posey and Eddie House. I must fess up to thinking less of the team than just about every fan, at least until Posey and House came aboard. I would have been happy to see them make the playoffs and win a round or two. Obviously, they exceeded that modest appraisal.

To me, there was an approximate three-year window in which to get the big job done and bring home championship No. 17. They took care of business immediately. But let's say, for the sake of argument, they didn't. Let's say they had not gotten past Cleveland, let alone Detroit. Would that have made them uninteresting, less entertaining, and just plain unworthy?

Don't be ridiculous. What the Celtics did was provide many nights of superb entertainment. The fact is there are 82 opportunities for them to display their artistry. It's about those nights as much as it's about these April, May, and June nights. Anyone for whom the playoffs are all that matters is bound to be disappointed.

What we've learned from this postseason is that the nightly entertainment promise has a good chance to be maintained, even as the Big Three are phased out, in whatever order, and however gradually.

The primary reason, of course, is Rajon Rondo.

We can table the matter of just where Rondo ranks in the NBA point guard hierarchy. What matters is that he is a truly electrifying player, and we have to assume he isn't going anywhere. The Celtics must pay up now, and how can they not, after what Rondo has done against Chicago and Orlando?

The Celtics' all-time point guard roster isn't bad, what with Bob Cousy, K.C. Jones, Jo Jo White, Tiny Archibald, and Dennis Johnson (not a true point, but no matter) all quarterbacking championship teams in the '50s, '60s, '70s, and '80s. The bar is set pretty high around here, one must admit.

So let us say this about Rondo: In terms of sheer entertainment value, contemporary Celtics fans may be getting the best deal. How can anyone who has been privileged to have seen all the aforementioned greats look any young Celtics fan in the eye who may not have seen any of them and say that Rondo isn't the most fun to watch of them all?

I didn't say he was better than The Cooz or Tiny or DJ, but he sure is different. He has a style all his own, and I, for one, look forward to every game he plays, because there really is a chance I'll see something I've never seen a Celtics point guard (or any point guard) do. And his dazzling moves are not just for show. The kid does stuff that wins games.

Now, how about "Big Baby"?

Start by saying that Glen Davis has exceeded all reasonable expectations since taking Garnett's spot in the starting lineup. How he'll respond when he is asked to resume being a primary sub next year is another matter, but the fact is he is a fine NBA player who should be an asset for years to come.

Next up: Kendrick Perkins.

Boy, was I wrong about him. I practically slandered this young man in the summer of 2007, declaring him to be, if I recall correctly, "a career backup." That calls for a major mea culpa.

Perkins is a very good rebounder. He is both a good individual defender and good team defender. He sets a mean pick. He has a reliable turnaround jumper and a reliable jump hook. Best of all, Kendrick Perkins knows exactly who he is on the basketball floor, and you can't put a price tag on that.

He may have improved greatly in the past two years, but it's clear there was a lot I just didn't see.

Throw Leon Powe into the mix. The problem now is that we don't know if his current injury has resulted in one knee surgery too many, but if he does recover the Celtics have a potent inside force who is capable of a double-double every time he steps on the floor.

These four young men are good players. I'm not promising any post-Big Three championships, but I am promising a team worth watching.

That's all anyone can rightfully ask for.

Bob Ryan is a Globe columnist and host of the Globe's 10.0 on Boston.com. He can be reached at ryan@globe.com.