“Gunsmoke” ended its 20-season run on CBS on March 31, 1975, the same night John Wooden ended his 27-season run as UCLA’s basketball coach.

Wooden went out in a blaze of glory, beating Kentucky for the NCAA title. “Gunsmoke” never really went away.

More than four decades later, the fabled western drama has not lost its swagger, regularly winning ratings shootouts with much of what modern media has to offer in reruns at 3 p.m. on TV Land.

Cute. But what does that have to do with sports television?

This: The show’s performance relative to other viewing options has become an unlikely parlor game for some of the journalists and fans who follow the sports media business.

The driver is the Twitter feed and website “Sports TV Ratings,” produced anonymously (until now) by Robert Seidman, a co-founder of the site “TV by the Numbers,” which Tribune bought from him and co-founder Bill Gorman in 2014.

Seidman said the kernel of the idea began with Gorman, who created the “Gunsmoke Rule” on the original site, which cautioned against making historical ratings comparisons because of the vastly changed television landscape.

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In 1959-60, “Gunsmoke” averaged a 40.3 rating, an inconceivable figure by modern TV series standards and thus not useful for current ratings discussions.

“His premise was, compare [shows] to last year’s ratings, but do not go beyond that, because it just doesn’t make any sense,” Seidman said.

Fast-forward to 2016, and “Gunsmoke” ratings serve a different purpose, which in part is to illustrate how relatively insignificant the skirmishes over much of sports TV are in a fractured media universe.

Seidman had noticed daytime cable sports TV data often was dull and uneventful, so he began “tinkering” with how to make it interesting and struck upon comparing viewership to “Gunsmoke,” of all things.

Take Monday.

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Even on a day that includes ratings givens such as “Monday Night Football” and the “SportsCenter” that follows it, “Gunsmoke” was beaten by only seven of the 276 sports programs that appeared on cable channels.

“Gunsmoke” averaged 676,000 viewers, beating the combined totals of two much-discussed debate shows, ESPN’s “First Take” (312,000) and FS1’s “Undisputed” (131,000), starring former “First Take” star Skip Bayless.

“We spend a lot of time on how much money does Skip Bayless make or how much is Stephen A. Smith enabled by ESPN and all those things, and nobody talks about, ‘How much did TV Land pay for all those ‘Gunsmoke’ episodes?’ ” Seidman said. “By the way, I don’t know the answer to that, but I would love to.”

There are important caveats here: As you might expect, “Gunsmoke” demographics skew extraordinarily old. Of the 676,000 viewers Nielsen estimated for Monday’s 3 p.m. show, only about 74,000 were under 50 years old.

“First Take” (168,000) and “Undisputed” (87,000) both had more viewers ages 18-49 than did “Gunsmoke.”

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Also, Seidman said it is a bit unfair to compare “Gunsmoke,” a singular attraction for fans, to the varied options sports viewers have.

“With the people who watch ‘Gunsmoke,’ there’s just not a lot of stuff they can do that reminds them of what life was like 50 years ago, and for a lot of people I think that’s just comfortable,” he said. “It’s comfort food for certain people . . . But there’s a ton of options for sports debate programming, and so I see it as more fragmented.”

Fair points. But still . . . “Gunsmoke”?!?

Seidman, 54, said he likely could have found similar numbers using other long-ago shows now in reruns. But why not give some 21st-century love to Marshal Matt Dillon and his friends?

“It’s just to be quirky and amusing,” Seidman said, “and to make something rote and boring a little more interesting.”