Dallas ? Four days to go now, and it’s all about survival. By Sunday night, it will all be over.

No, this isn’t about March Madness and the announcement of the men’s basketball tournament field. I’m talking about surviving one final week of ads for ESPN’s “Season on the Brink.”

You know, “Brian Dennehy IS Bobby Knight.”

Sorry. From the looks of the trailers, Brian Dennehy IS Brian Keith. Brian Dennehy MIGHT BE Willy Loman. But Brian Dennehy IS NOT Bobby Knight.

It’s a good rule not to critique a film (using that term broadly) you’ve never seen or trash a book you’ve never read. So it should be said here that the made-for-March-Madness-movie just might provide a wonderful evening of entertainment as long as you can ignore the fact that the lead actor looks and sounds and acts nothing like Knight.

Recall that John Feinstein’s book was about the 1985-86 season. That’s 16 years ago. Knight was hardly a frumpy, old man at that stage of the game. And yet we get Brian Dennehy?

Where was Craig T. Nelson? At least he knows how to play a coach. At least he knows how to be nasty.

The real problem here is that when it comes to sports non-fiction, even best-selling sports non-fiction involving popular and controversial figures, filmmakers shouldn’t bother. When it comes to watching movies about athletes and coaches that they have spent (too much of) their lives following, sports fans are as meticulous about accuracy as war buffs. And you know how those people can be.

“Did you see those miniballs they used for the battle of Little Round Top in Gettysburg?”

“Yeah. Wrong size by a half-inch. Ruined everything.”

Of course, we don’t have to be employing too fine a microscope to say that neither John Goodman nor William Bendix made any sense as Babe Ruth, that LeVar Burton was about half the size of Ron LeFlore, that the great Ray Liotta couldn’t even bring himself to bat from the correct side of the plate as Shoeless Joe Jackson.

Now you can play a boxer if you have the physical endurance to work at it.

But sports characterizations are rarely a launching pad for acting careers.

There was a time when sports movies at least had a chance to succeed. They had a place and filled a void that disappeared even before ESPN took over the planet.

I know Yankee fans who still swear by Gary Cooper as Lou Gehrig in Pride of the Yankees. While it’s difficult to picture Gehrig tripping over bats as he emerges from the Yankee dugout, Cooper could play the role as he chose because fans didn’t see Gehrig on daily television or nightly highlight shows.

He could capture Gehrig’s spirit without viewers saying, ‘That’s not how he talks. That’s not how he walks.”

Today, we don’t need movies about Tiger Woods (even though we got one, directed by LeVar Burton, no less). We turn on the TV and see the real thing 22 weekends a year. Some would say that’s enough.

Lots of folks have had enough of Knight, too. Some haven’t. My guess is they won’t learn much they don’t already know by tuning in Sunday night.