They say hindsight is 20/20, and that’s certainly true in the case of 74-year-old Suzan Marciano and her golden retriever mix Nalu, who live in Boca Raton, Florida.

The two were out for a stroll in nearby Burt Aaronson Park at around 6:30 p.m. on Aug. 24 when the day took a turn for the worse.

The lake at the park is often used for water skiing, and the clear, shallow water looked inviting.

So Marciano unclipped Nalu’s leash and started a game of fetch, tossing a stick into the lake for the water-loving pup to retrieve.

As she got closer to the water’s edge, Marciano caught a glimpse of something in the clear water: A dark shadow. And it moved.

“My heart dropped,” she told The Palm Beach Post.

The 6-foot-alligator lunged and quickly bit down on Nalu. Marciano reacted on pure instinct.

“I wasn’t thinking,” she said. “I did the only thing I could do. I came down on the alligator with all my weight.”

The alligator released Nalu and turned its attention on Marciano, biting her hand instead.

“Providence must have been with me,” Marciano said. “It was all one big blur. I was in such shock. I didn’t feel any pain.”

While Marciano was hesitant about getting medical attention, a friend was able to convince her to go get her hand, which had a puncture wound in the palm area, checked out. She ended up with five stitches.

“I almost didn’t go,” Marciano said of getting her hand looked at. “All I could think was, ‘I want to get home.’ I was in such a terrible state that I wasn’t thinking straight.

“When I called her, she told me, ‘You have to do something. You need a tetanus shot and you need the injury looked at.’ That snapped me back to reality.”

Nalu required much more extensive care, including surgery and stitches in her abdomen and thigh. She was definitely a little down in the following days.

“I had this feeling that she was going to survive,” the owner said. “If she survived that, she can survive the surgery.”

Since the incident, the pair has avoided the park. It took a few weeks before they went back.

According to an incident report obtained by The Palm Beach Post, both a park ranger and a Florida Fish and Wildlife Commission officer returned to the park but found no sign of an alligator in the lake.

Dog owners, especially those who live in a similar area as Marciano, are appalled that she let her dog play in the water. Many dog-walking locals stay far from the water, knowing that the giant reptiles are eager for doggie hors d’oeuvres.

Thankfully Marciano and Nalu will both be able to learn from the encounter, and hopefully they’ll enjoy many more walks together in less dangerous ways.

“I hardly went anywhere for two weeks afterward,” Marciano said. “I was in such a traumatic state. Every couple of hours, I was breaking into tears for no apparent reason.

“I was still seeing the shadow with two eyes looking up from out of the water. That image kept coming back to me.”