Yankees first base coach Reggie Willits holds back Brett Gardner...

Yankees first base coach Reggie Willits holds back Brett Gardner as he argues with first base umpire Phil Cuzzi during the sixth inning against the Cleveland Indians at Yankee Stadium on Saturday, Aug. 17, 2019. Credit: Kathleen Malone-Van Dyke

You remember the old saying, “It’s all fun and games until someone loses an eye”? It’s right up there with “Mom and Dad always said, ‘Don’t play ball in the house.’ ‘’

Well, Brett Gardner banging his bat on the dugout roof as a way to get the Yankees fired up is all fun and games until Major League Baseball lets him know he should stop doing it. Or until it costs the Yankees something.

That’s the subtext to the wild scene that unfolded in the bottom of the sixth inning on Saturday in the Yankees’ 6-5 victory over the Indians.

Gardner’s antics did cost the Yankees something – his services after he was ejected from the game. The Yankees are just lucky it didn’t cost them more.

Yankees manager Aaron Boone had just been ejected by plate umpire Ben May for arguing a questionable called third strike to Cameron Maybin and was on his way back to his office when first-base umpire Phil Cuzzi sprinted toward the home dugout and ejected someone.

It was Gardner, who had decided to bang the fat end of his bat on the inside roof of the dugout even though he knew MLB wasn’t thrilled the last time he did that on Aug. 9 in Toronto. On that occasion, Gardner did it after a questionable strike call (also, coincidentally, against Maybin).

Gardner was ejected from the Aug. 9 game in what turned out to be a case of mistaken identity because umpires blamed the intense 35-year-old for yelling from the dugout when it actually was Maybin.

Still, MLB executive vice president of operations Joe Torre (yes, that Joe Torre) later said he felt the Aug. 9 ejection of Gardner was justified. Even if Torre’s explanation was strained – it seemed to be based on actions Gardner took after he was tossed – Gardner and the Yankees had to know MLB would be watching in case he decided to take bat to roof again during or after an incident with the umpires.

On Saturday, after Gardner was ejected, Boone put infielder Thairo Estrada in rightfield with Mike Tauchman moving to center (bypassing the resting Aaron Judge). The Yankees were fortunate it didn’t bite them in the fanny in a one-run game.

What if Estrada botched a fly ball and the Yankees lost? Remember, it was Gardner who made a great catch in right-center in the eighth inning on Friday night to seal another one-run victory over Cleveland.

Sure, the Yankees have the AL East title in sight, but they will be the first to tell you they have clinched nothing yet. And there’s the battle for best record in the American League with Houston, which could be a factor if the teams meet in the ALCS. Every game counts.

Gardner’s passion is admirable. His inclination -- and the Yankees’ -- to ignore MLB’s obvious distaste for his roof-banging is not.

Boone said he was not explicitly told that banging one’s bat on a dugout roof is an offense that will get you ejected. Gardner said he wasn’t told that, either. It’s another odd coincidence that Gardner ran into Torre on Saturday as the former Yankees manager was at the stadium for Mariano Rivera Day.

Gardner called the encounter “awkward,” which makes sense. It’s not the first time he’s been at odds with Torre. Just last season, Torre sent Gardner a letter informing him he was being fined for ignoring repeated warnings about walking to the plate too slowly before his at-bats as part of MLB’s quest to speed up the game. Gardner was livid.

This time, MLB should be faulted for not explicitly telling Gardner to cut it out. MLB certainly hinted at its feelings about the roof-banging, but there was no reason after the Toronto incident for Torre not to get out his pen and send a “Dear Brett” letter asking him to keep his bat in the rack.

“Splinter danger is real,” it could have concluded. The team also could have reminded Gardner that he needed six stitches in his lip in June after getting hit by his own helmet when he fired it down after being robbed of an extra-base hit.

There are other ways to fire up your teammates. The weirdest thing about Gardner’s decision to grab his lumber on Saturday is that he was standing calmly with his arms folded on the dugout railing as Boone was getting ejected (and getting his money’s worth during the argument).

So while the Yankees can say it was in the heat of the moment, there was no heat in that moment for Gardner. It was a choice.

“I probably won’t do it again tomorrow,” Gardner said. That’s probably a better choice.

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