One of the big mysteries surrounding Seattle’s overtime victory against Denver on Sunday was just how that game ended up in overtime anyway.

Yeah, we know Peyton Manning and the Broncos pulled off a nearly impossible task, marching 80 yards in 41 seconds with no timeouts and converting the two-point conversion to force overtime.

But how did it happen?

Pete Carroll provided the answers Monday.

“There was one concept that they threw at us that we misplayed,” the coach said. “They threw it four times in a row. We stopped the first. The second one got us. The third one we think we’re OK and the fourth one scored the touchdown.

Carroll said Kam Chancellor’s unintentional wind-sucking blast of nickel back Marcus Burley — sending him to the sideline — on an incompletion to Emmanuel Sanders led to the Broncos’ success on the second play — a 42-yard completion to Sanders down the same sideline against No. 4 corner Josh Thomas.

“It was unfortunate that Marcus was all revved up for the scheme, the first one, and that’s when Kam knocked him out,” Carroll said. “And then Josh got off the bench and they came right back and hit the exact same play.”

Carroll said he tried to warn Thomas as he headed onto the field, but the message was lost on the newest Seahawk, who has been with the team for less than two weeks.

“Then they got K.J. (Wright) later on in a similar situation (26-yard touchdown pass to tight end Jacob Tamme), so they did a really nice job,” Carroll said. “It’s just a raw principle that we didn’t play well, and (Manning) took advantage of it and did a great job.”

Carroll said the Broncos had “two significant plays” in the game, and both came on the tying drive.

“And they had a great execution on the two-point play, too,” he said. “Richard (Sherman) was trying to shove him (Demaryius Thomas) out of bounds. … It was a great throw and catch.”

“We really felt very much in control in that game,” Carroll said. “Unfortunately, we let them back in there at the end.”