That Joni Mitchell song nailed it: “Don’t it always seem to go / That you don’t know what you’ve got ’til it’s gone?”

Saturday, what used to be the rule became the exception. Sunday, what once was impossible continued to be the rule.

With its play-by-play troops thin, YES called in call-up reliever Bob Costas to call Saturday’s Red Sox-Yankees doubleheader.

The last time Costas made his Saturday baseball mark here was throughout the 1980s as the play-by-play man or studio host of NBC’s Saturday “Game of the Week.”

Viewers seemed divided on Costas. Some, such as I, appreciated his honesty, great regard and concern for baseball and well-targeted cynicism. As the host of World Series telecasts, he’d anger his bait-and-switch NBC bosses by revealing the time of the scheduled first pitch.

Others, however, found him condescending and too embracing of the T-word — traditionalism — as if he were the sole and slightly smug guardian of The Game and Stan Musial artifacts.

But this past Saturday, gauging by the large response from readers, Costas’ return — at 67, he still calls MLB Network games — was overwhelmingly enjoyed as a throwback to when TV didn’t devour all our sports by dazzling us with video and audio junk.

For seven hours, without relying on trite expressions, dubious stats, obsequious hype or seminars on splitters and changeups, Costas served as our intelligent guide and interesting storyteller through both games.

Not that he didn’t risk what he always risked: the wrath of MLB. He made it clear that The Game is in trouble, as it has lost or sold its soul — from hit-and-runs to bunting to hitting with two strikes — to bushels of redundant game-decaying strikeouts in pursuit of home runs.

Sunday night, however, it was back to the rock pile. After a 1:10 rain delay as per meteorological analytics only in anticipation of rain, Red Sox-Yankees began to the usual question: “How does ESPN continue to believe that these productions are better than awful?”

Smarmy, trite, say-anything play-by-play man Matt Vasgersian was again too busy talking to know what he’s talking about. Thus, when Gleyber Torres led off the bottom of the first with a ground out, Vasgersian identified it as “the first out of the game” — three outs too late.

It’s the same with nonstop, say-anything Alex Rodriguez. In the top of the third, Rafael Devers batted with men on first and second. Rodriguez: “Devers is very aggressive … but make a quality pitch, double play, you’re out of there.”

Devers then hit a DP ball to first. “Like that,” said Rodriguez in self-fulfillment. But the Yanks only went for one out — likely because there already were two out!

The telecast began with a salute to DJ LeMahieu as a complete player and MVP candidate hitting .336. Rodriguez endorsed the notion.

But later, Rodriguez declared the preposterous to be true: Homer-or-strikeout Gary Sanchez, who has little in common with winning baseball (last year he hit .186, this year he was at .229) is “the best hitter on the Yankees.”

After Aaron Judge homered in the first, ESPN spent the next three innings dissecting, discussing and applying it to computer imaging, exit angles, launch velocities and even its apex chart. Is an apex of 120 feet good or can that also be a pop-up?

Before the first ended, six replays of the HR. Another in the second. In the third, Jessica Mendoza narrated the seven-pitch sequence that, according to her, explained why he hit the home run. Then two more replays of it.

Rodriguez even got the self-evident wrong, claiming Judge’s homer landed “way up in the upper deck in right-center field.” There is no upper deck in right-center. It landed in the bleachers.

Regardless, ESPN is complicit in the ruin: Home runs are baseball and baseball is home runs. Like slam dunks and 3-point bombs, all that matters is, Boom!

Giant sigh of relief at no Mike

A few weeks before their NFL opener, the Giants are in a terrible bind. Mike Francesa, who never tires of being a public jackass, this week declared he has declined his annual invite to conduct his show from Giants camp because general manager Dave Gettleman “should have enough confidence and conviction to explain his decisions. If he’s hiding, I’ll pass.”

Shucks! Now we lose the opportunity for Francesa to tell Gettleman and every member of the Giants what he thinks and how he would run the Giants.

As if Gettleman must answer to him! (Or is it Him?)

Francesa’s irreversible megalomania and rotten guesswork is such that we’re supposed to forget that in late April, he trashed the Giants as “a laughingstock around the league” for drafting cornerback Corey Ballentine, accusing the kid of rotten character after he soon “got shot on a Saturday night.”

He had no idea that Ballentine was considered a young man of high character who was shot — his pal murdered — in what still seems a random drive-by.

Perhaps it was Francesa who ducked Gettleman rather than face that music. Or perhaps Gettleman was prepared to ask Francesa to explain his proven lie — as per Bob’s Blitz — claiming the Pentagon solicited his advice on how to fix Army football.

Francesa boycotting the Giants? He’ll show them! He’ll predict an 0-16 season for them!

Whiz’s FIBA try at test-fix pregnant with absurdity

Former Ohio University men’s basketball player D.J. Cooper has been banned by FIBA from continued international professional play after his urine turned up clean. Huh? FIBA alleges he used urine supplied by a pregnant woman, as if there’s any other kind. Cooper is due in December.

It doesn’t matter if their teams are in first or last, MLB managers now play to lose.

Monday against the Yankees, the Orioles came back from five down to tie it at six. O’s reliever Mychal Givens next faced five Yanks, allowing one walk and retiring the other four on a total of just 18 pitches.

But Baltimore manager Brandon Hyde gave him the hook for Paul Fry, who next, in two-thirds of an inning, allowed two home runs and three earned runs. With Hyde’s aid and comfort, the Yankees won, 9-6.

On that subject, reader Ed Finkelstein suggests a headline for the Astros’ four-pitcher no-hitter: “Astros No-Hit Mariners As Manager Fails To Find Pitcher To Allow A Hit.”

Reader Bruce Christoffersen on why Domingo German has no chance to win the Cy Young: “He has too many wins.”

Finally, reader Steve Oleynek has more proof something’s rotten with the baseballs: “Last year, Trevor Bauer wouldn’t have been able to throw it beyond the warning track.”