While the internet seems certain the shirtless Islanders proposal was a fugazi, an eyewitness believes it was a genuine rejection.

During Thursday night’s game between the Islanders and Panthers, a fan took off his shirt and proposed to his girlfriend. She said no.

David Marcus, a 17-year-old Islanders fan who lives in Brooklyn, was at the game with his father. They were in section 118, row 19, one row ahead of the couple.

Marcus told The Post that at first he thought it was a run-of-the-mill Kiss Cam moment. “I didn’t think anything of it,” he said. But when Marcus went to go make a funny face behind them kissing, he was stopped by an arena worker who told him, “No, don’t do that. Something’s about to happen.”

“Marry You” by Bruno Mars came on the PA, and Marcus started recording on his phone.

“The guy takes his shirt off and it says, ‘Please say Yes Yes Yes,’” Marcus said. “And she was shocked. I heard her say, ‘What? What’s happening? We can’t do this!’ And then he yells, ‘Oh f–k!’ Everyone was taking a video, and the crowd was going crazy. When she started walking up the stairs, everyone yelled, ‘Awww…’ It was crazy.”

Marcus does not believe this was a moment that was staged to go viral.

“After the woman ran up the stairs, the guy told my father, ‘Wow, I’m sitting here in front of 20,000 people without a shirt. This is pretty embarrassing.’ Right after this happened, the Florida Panthers scored a goal. The guy told my Dad, ‘Wow, this is really a bad omen.’”

Marcus’ father told the young man that the woman would come back to him and say yes. The rejectee was not so sure.

“He was holding the ring. He was tearing up, and he was very embarrassed,” Marcus said. “And then he just ran up the stairs with her purse — she left her purse there — and then we never saw them again.”

If this was indeed all a ruse, it was a very elaborate one.

“Some people on Twitter are saying she was already wearing a ring. If she was, I didn’t catch that,” Marcus said.