AUGUSTA, Ga. — If you saw the video footage, it wasn’t far removed from Joe Theismann’s leg being snapped in half by Lawrence Taylor on the 1-to-10 scale of gruesome.

If you saw the footage of Tony Finau dislocating his left ankle while celebrating his hole-in-one at Wednesday’s annual Par-3 Contest, you’d have bet your mortgage that Finau would never make it to the first tee to play his first Masters on Thursday.

Finau was destined to become the saddest Masters story this side of Greg Norman’s 1996 final-round collapse and Roberto De Vicenzo signing an incorrect scorecard and disqualifying himself from a playoff with Bob Goalby for the green jacket.

“What a stupid I am,’’ De Vicenzo famously said after that gaffe.

Finau — who was backpedaling in celebration of the ace, with his wife and kids caddying for him and looking on, caught his left foot in the turf and crumpled to the ground with his ankle looking mangled — can relate.

“It was a pretty cool moment followed by probably one of my most embarrassing moments, and a scary moment at the same time,” Finau said.

And it was all followed by a rather miraculous moment: Finau making his 12:43 p.m. tee time and then shooting a 4-under 68 to lead the Masters until Jordan Spieth overtook him for the lead at 6-under later in the day.

“To me it’s nothing short of a miracle that I’m sitting here right now,’’ Finau said. “My foot was out of place 24 hours ago and I sit here now in second place at the Masters after Round 1. When it happened, I felt like there probably could be something seriously wrong. I could barely put any pressure on it. I could barely walk.

“The emotions have been pretty crazy. I’ve looked forward to this week for a really long time, and to see the possibility of that slipping away … waiting for another opportunity to play my first Masters, whether it was next year or another time, was going to be hard for me to swallow.’’

Finau dislocated the ankle, which he popped in place as soon as he fell, and the official diagnosis was a high ankle sprain. NFL players with high ankle sprains miss weeks. Finau is in second place at the Masters, 24 hours after doing it.

“Once you see the video, the video speaks for itself,’’ said Gregory Bodine, Finau’s caddie the past four years. “I knew that if anyone could do it, he could do it.’’

When the two men walked off the 18th green after the round, Bodine told Finau “how much heart he has.’’

“You can’t not have heart and play a round like that,’’ Bodine said. “He’s worked his whole life to get here. If you know Tony’s story, he’s fought way too long and hard to get to this point.’’

The heart of Finau’s story is his mother, Vena.

Vena Finau wasn’t at Augusta on Thursday with Tony’s dad, Gary, and the rest of the family because she was killed at age 47 in a car crash late in 2011, when his sister, Nola, lost control of the family’s vehicle and rolled it while returning to Utah from a wedding in Reno, Nev.

Nola and the eldest son of the seven Finau children, Kinga, survived the crash.

It was Vena Finau’s vision that set her son Tony on this journey. She pushed Tony and his brother Gipper into golf as a way to deter them from joining the street gangs that were infesting their Salt Lake City neighborhood.

“I think God and his mom are there with him and probably rewarding him for listening,’’ Gary Finau told The Post several years ago.

Gary Finau was at Augusta Thursday and, in between tears, he spoke of the wild swings of emotions that the family had endured the previous 24 hours.

“Yesterday was devastating,’’ Gary Finau said. “We believe this is a holy ground, so we did a lot of praying. When we saw it happen, yeah, it was pretty graphic. We were thinking we were going to pack up and watch it on TV where we’re staying and just feel sad.’’

Then Gary Finau, not trying to be funny, said, “What do we do? Teach him how to celebrate better? I told him, ‘You say you’re an athlete, but you can’t celebrate? So that’s going to take that athlete status away.’ He was like, ‘I’m going to go prove that wrong tomorrow.’ ’’

So he did.