In 60 years of watching baseball, it took until Thursday night to finally put my wrinkly, crooked index finger on it. I realized what has been right in front of me the past five seasons: Yankees catcher Gary Sanchez, a two-time All-Star, knows almost nothing — nothing — about how to play baseball.

It seem as if several times per game he shows himself to be totally unfamiliar with the sport, beyond swinging as hard as he can to try to hit home runs.

Everything else either throws him or escapes him.

Thursday against the A’s in Oakland, Sanchez led off the second with an, oops, line-drive single. The next batter, Brett Gardner, hit a hard grounder to first — the ball’s first bounce was immediate, just a few feet beyond the plate — yet Sanchez was seen running toward second at a minimized pace because he was looking back toward first.

What did he expect to see at or near first? I don’t know. A pink flamingo?

If he wanted to see a force play on Gardner, he did. But why he didn’t head directly toward second on a ground ball was more hard evidence that Sanchez doesn’t know enough about baseball to know how it should be played.

With the throw from first now headed toward second, Sanchez only needed to slide to beat that throw — it would be high and wide — as the force was no longer in play.

But Sanchez awkwardly pulled into second, standing, then, trying to elude the tag, fell off balance then off the bag before he was tagged out to complete a double play.

Even by today’s diminished skills and standards, this was a double play that appeared as the residual of Sanchez, yet again, failing to recognize or practice elementary, remedial common sense baseball.

On YES, the first words heard were, incredibly, praise for A’s first baseman Matt Olson for a fine, head-up play. Huh? He fielded a grounder, stepped on first then threw wildly to second? Fine play? Only as fine as Sanchez allowed.

During a replay, David Cone said, “For some reason Sanchez didn’t slide.” For some reason? It was the same reason — Sanchez doesn’t know how to play the game. But in 2019, as long as he hits home runs, that’s plenty good enough.

Cone concluded it “was a weird play.” Weird? No. Why? It was the logical conclusion to Sanchez’s illogical, organization-indulged sense of baseball.

And game after game we have to suffer such ignore-the-conspicuous commentary as if we’re too stupid to know better.

Sanchez plays his position as if under a spell, a fog that fills him with indifference. He runs the bases — when he’s in the mood — as if he’s lost beyond anything more challenging or thought-worthy than a home run trot.

But to pretend that we can’t see or recognize when players are the victims of their own deficiencies — not the victims of superior play by opponents — is insulting to viewers who know and deserve better.

How to fail: Play by the book

Reader Rich LePetri on Tuesday met a female college friend, a casual baseball fan, at the Indians-Mets game. After Mets reliever Jeurys Familia entered in the fifth and made 1,2,3 on just 10 pitches, he was removed by Mickey Callaway.

LePetri’s friend asked why Callaway would pull Familia. LePetri was stuck for an answer. He still is — even a bad one.

The fantasy persists among managers that all their relievers, in order and on daily command, will be lights-out, when managers should be grateful to succeed with and sustain just one in-a-row.

That’s why Rays manager/script consultant Kevin Cash, with a 4-3 then 5-3 lead Wednesday vs. the Mariners, removed two consecutive effective relievers — one hit allowed between them in three innings — for “closer” Emilio Pagan, who was crushed, then awarded with the blown save and telltale/bad-tale win.

Pagan is the latest in a series of Rays closers. This season he’s 3-2, seven blown saves. But Cash, again, was intent on finding the reliever who’d be crushed, and he found him. Relentless epidemic of managerial insanity.

Sportscaster, studio host and essayist Jack Whitaker — wounded on D-Day at Normandy — died last week at 95, having outlived his fame. He’d been largely forgotten or unknown.

But he was pure class — a mature, literate and thoughtful presence, mostly on CBS then ABC. He’d ask us to think along with him and to consider the human condition, no sermonizing, just well-chosen words.

Would Whitaker be hired today? For what? As what? To recite exit velocities? Red-zone stats? Holler over slam dunks? Interview Odell Beckham Jr. to pull some self-smitten, trash-talk sound bites? Host or report the results of home run derbies?

Like Vin Scully, Marty Glickman, Chris Schenkel, Jim McKay and Ray Scott, among others, I doubt Whitaker would be asked for an audition callback. No shtick, no hollering, no hype, thus not interested.

Mets are loyal to the night owls only

Given that the Mets no longer play early Saturday afternoon games, emails from those who were baited-and-switched by the ESPN/MLB change of Sunday, Sept. 15’s Dodgers-Mets from 1 p.m. to a night game, have grown.

One came from a mom who was to host her son’s birthday party at Citi Field that afternoon. Her kid and his 12- and 13-year-old pals and kin were all charged up. Now? Forget it.

Still, Rob Manfred declares that on his watch, kids are MLB’s top priority.

Need a good cackle? Check out Mike Francesa’s revisionist take on this year’s Mets, as seen and heard on the @backaftathis Twitter feed. What a spectacular, 180-degree phony! Francesa has never been right in foresight, never wrong in hindsight.

As seen on TV: Everywhere the Yankees play outside of Yankee Stadium presents the inverted, 10-years-of-untreated-greed reality of new Yankee Stadium. Last week in Toronto, then Oakland, the good seats were seen filled, thinning as they headed up and out.

Last week, Nebraska, “Big Red” — school colors scarlet and cream since 1892 — unveiled its new, what-a-coincidence, black football uniforms.

Manfred Meatballs Game of the Week: Sunday, Nationals 16-8 over the Brewers in 8½ innings. There were, yawn, 12 home runs.

Though I’d rather watch my sister-in-law play Canasta than preseason football — she’s an undrafted free agent — twice this summer I’ve tuned in to hear that a team’s defense “wants to get off the field.” If that’s the case, why get on the field in the first place?