Who let the air out of the ball last night at the Republican debate in Coral Gables?

Talk about Deflategate — after 11 nights of Texas death matches, suddenly they were pulling their punches. Donald Trump because he’s won, and the other three because they’ve … lost.

“All of a sudden I can’t believe how civil it’s been up here,” Trump said with a smile at 9:34 last night. Death has five stages, the final one is “acceptance.”

Ted Cruz can blame it on a cold, John Kasich can blame it on his strategy, which if you had to put it on a baseball cap would be, “Make America Boring Again.” As for Marco Rubio — is it too late to drop back and run for his Senate seat again?

Little Marco had the whole crowd with him right there in Dade County, but he still couldn’t bring his A-game, which left Trump to start spring training for the general-election debates. To use the consultant cliche, he’s “pivoting.”

Trump is running out the clock. But if it’s football, you still have to mix it up. You can’t run off tackle every play, right? So when Jake Tapper asked him about his comment on CNN that “Islam hates us,” Trump has the perfect comeback.

“A lot of ’em do.”

Can anyone deny that? Rubio couldn’t. He had to admit the “significant problem.” Rubio uses his focus-group-tested lines like, “I don’t want to be politically correct, I want to be correct,” but now everyone is onto his schtick. With Trump lying low last night, it was easy to see how correct he was when he said there would be no record audiences without him. The same old people were coming after him — like Hugh Hewitt, the radio talk show host who did everything in 2012 except ask Mitt Romney to marry him.

So when Hewitt came after him on Israel, Trump shrugged and mentioned that his daughter and his son-in-law are Jewish.

Somewhere last night, if he was watching the debate instead of doing one of the hundred cool things he claimed he could be doing if he wasn’t running for president, Jeb Bush had to be asking himself:

“Why didn’t we have any debates like this when I was running? I could have been this boring.”

And don’t you think Carly Fiorina and Chris Christie and Bobby Jindal and Rick Perry and Ben Carson and all the rest of them were thinking the exact same thing? They could have been contenders …

Cruz kept talking about “the rules of engagement.” Trump changed them last night, and the others couldn’t do anything about it. The polls were off on the Democrats in Michigan, but obviously the Republicans in Florida think they’re spot on, and they’re just trying to survive without being routed. Of course, sometimes they forgot they’re not dead. Shortly after 10 last night, Little Marco said, “When I’m president …”

When you’re president? Hey, Little Marco, keep your arms out. It’ll make it harder for the guys in the white coats to throw the net over you.

Big loser: CNN. I’ll bet this was Trump’s last GOP debate. I’m sure it was the same for 10 million Americans.

Listen to Howie 3-7 p.m. every afternoon on WRKO AM 680.