Detroit coach Dan Campbell said he explained to officials before playing the Dallas Cowboys what would happen on a 2-point conversion play the Lions had planned.

Chaos ensued anyway, and left the Lions feeling as if a victory was taken away from the NFC North winners in their pursuit of the top seed in the NFC playoffs.

Officials ruled offensive lineman Taylor Decker wasn’t an eligible receiver when he caught a 2-point conversion pass that would have given Detroit a one-point lead with 23 seconds remaining.

Instead, the Lions (11-5) lost to the Cowboys 20-19 on Saturday night when the third 2-point try was an incomplete pass short of the goal line.

Jared Goff threw an interception on the attempt after Decker’s catch was disallowed, but Dallas was offsides.

The explanations contradicted each other, with Goff saying he was certain Decker reported as an eligible receiver and Dan Skipper had not. In a pool report, referee Brad Allen said the opposite, that Decker didn’t report and Skipper did.

“I don’t want to talk about it,” said Campbell, who was visibly angry with Allen when they talked after the officials made the ruling. “I explain everything pregame to a tee, OK? I did that.”

Allen said Skipper, a backup tackle, reported to him as an eligible receiver, but then went to tackle spot, which meant he didn’t have to report at all. Decker, the starting left tackle, was already in the game.

Video showed Decker having a conversation with Allen, who then said something to the Dallas defense.

“That conversation is where (Skipper) reports to me, and I then go to the defensive team, and I say to them ‘(Skipper) has reported as an eligible receiver,’ so they will be aware of who has reported and then I return to my position,” Allen said in the pool report. “That was the conversation with the defensive line.”

Decker’s conversation with officials came after Goff’s 11-yard touchdown pass to Amon-Ra St. Brown. Campbell said he had already told his team he would go for the win if the Lions scored.

“All I really want to say on it, just so I don’t get myself into trouble, is I did exactly what coach told me to do,” Decker said. “It was my understanding, too, Dan brings up the possibility of those sorts of plays pregame, so I did what I was told to do. Did how we did it in practice all week.”

Goff pleaded Detroit’s case as officials discussed what they were going to call.

“Very confused,” Goff said. “What I do know, and I don’t know if I’ll get fined for this, but I do know that Decker reported. I do know that Dan Skipper did not. I do know that they said that Dan Skipper did.”

The Cowboys (11-5) extended their home winning streak to 16 games — and finished the regular season 8-0 at home — by rallying from a fourth-quarter deficit at AT&T Stadium for the second time this season.

McCarthy said he was told Skipper was announced as eligible, but that Skipper lined up in a way that made Decker an ineligible receiver.

“That was a 2-point extravaganza,” Dallas coach Mike McCarthy said. “It looked like training camp, lining up and going at it for three or four plays. Great fight and finish by both teams.”