It began when CNN moderator Dana Bash brought up their ages, which are just slightly older than igneous rock. If elected, either would be the oldest president in history. It’s worrying people. What’s it going to cost to convert the White House for assisted living?

So as they boasted about what terrific shape they’re in, the subject of golf “handicaps” came up. In golf, every avid player has a handicap, and the lower the number, the better. If you’re a 10, that’s pretty good and means your average score is going to be about 10 strokes over par. If you’re a 30, that’s very bad and means you should probably take up pickleball.

Biden: “I got my handicap, which, when I was vice president, down to a 6.”

I slapped my forehead. Biden had shuffled to the podium like he was wearing leg irons, so nobody on Earth was believing he’s a 6. Trump yelped, “That’s the biggest lie, that he’s a 6 handicap, of all!” Biden immediately changed it to “8,” which only made things worse. It was like somebody saying, “Okay, wait. Now I remember. I didn’t knock out Muhammad Ali. I knocked out Joe Frazier.”

And yet … if you go to the U.S. Golf Association’s online handicap website, the handicap listed for Biden at Fieldstone Golf Club in Delaware is 6.7.

Pah. The site’s stats are only as fresh, and accurate, as the scores the player feeds into it, and Biden hasn’t entered a new score in six years. Looking at him today, you’d wonder if he could break 100. For nine.

Besides, why would you try to out-spit a llama? Go ahead, brag about your gym workouts or your bike rides; Trump has already cornered the market on outrageous golf fibs. He chronically tells passersby that he’s a 2.5 handicap, which is a whopper with cheese. Okay, the USGA’s handicap website lists him as a 2.5, but did I mention that they rely on the golfer’s honesty? Trump is no more a 2.5 handicap than Mitch McConnell is a break dancer.

I’ve played golf with Trump. He’s good off the tee, but he shanks shots, chunks chips and purloins putts. He’s actually about a 10 or 12 handicap, and that’s only with the help of his caddies, who toss balls out of bunkers and kick them out of the junk.

So, to recap, if Biden is a 6 handicap, elephants can Hula Hoop. And if Trump is a 2.5, they can do it on top of flagpoles.

Trump: “I’m in very good health. I just won two club championships, not even senior, two regular club championships.”

Okay, this sentence comes with so many lies I need an abacus.

At just about any country club, they have a yearly “club championship” for members. Usually, the top golfers of any age play over two days to see who’s best. All putts have to be sunk, all rules have to be followed. Trump rarely does either. Yet he somehow “just won” two club championships?

I’ve been around golf for half a century. I’ve never, not once, seen anyone over 55 win a club championship, to say nothing of a 78-year-old shaped like the Liberty Bell. Members I know at Trump’s clubs tell me I still haven’t.

Besides, I already know Trump doesn’t actually “win” club championships or even senior ones. He co-opts them, steals them and invents them. He once told me, back before his political days, that when he buys a new golf course (he has about 16), he plays the first “club championship” by his lonesome. Voilà! He’s the champ. He has also “won” a championship in New Jersey while he was in Philadelphia, “won” ones he never even entered and “won” another at one of his Florida clubs apparently while he was overseas hanging with Kim Jong Un.

At least in the debate, after the baloney about winning two club championships, Trump floated a golf canard I hadn’t heard before.

Trump: “To do that, you have to be quite smart.”

No, you don’t. I’ve met some of the world’s best golfers, and a few of those guys are so dense that light bends around them.

What Biden should have said at this point was, “Call us when you’ve won one at a course you don’t own, Donald.” Because Trump never has.

The whole debate went like that: Trump lying fatuously, leaving his chin wide open for a knockout punch, and Biden instead mumbling about Scranton.

Yeah, it was bad for Biden, but I don’t care. I’ll still take the old man over the con man. Debates are like golf. Sometimes you stink the joint up. I’m willing to give Biden a mulligan. God knows Trump would take one.