SANTA CLARA, Calif. — In a season in which the toughest question for the NFL to answer — on the field, at least — was, “Was that a catch?” it was appropriate that what might be considered the biggest play of Super Bowl 50 on Sunday involved such a vexing and controversial query.

On their way to a 24-10 victory over the Carolina Panthers, the Denver Broncos scored the game’s first touchdown on a fumble by Carolina quarterback Cam Newton, sacked near his own goal line. But that play would not have happened if the seemingly simple question — “Was that a catch?” — could be answered both simply and correctly.

Carolina, trailing 3-0, had first-and-10 at its 15-yard line with 7 minutes, 23 seconds left in the first quarter. Newton threw sharply to receiver Jerricho Cotchery, sprinting between the hash marks down the middle of the field.

Cotchery appeared to grab the ball at about the 35 after a bobble, and Broncos safety Darian Stewart quickly draped himself around Cotchery’s waist. Both men fell forward.

As Cotchery fell at the 38-yard line, the ball, in his left hand, appeared to be jostled as the back of his hand hit the ground. He pinned the ball under his right elbow as he rolled over, and the ball appeared to stay off the ground. But officials ruled the pass incomplete.

Carolina challenged the call. The replay review took several minutes, and referee Clete Blakeman returned the verdict: incomplete. The call stood, despite replays appearing to show that Cotchery’s hand, not the ball, touched the ground. There was no 23-yard reception.

“Based on what I saw, I disagreed with it,” Carolina coach Ron Rivera said after the game. “And the answer I got was that they didn’t have enough evidence to overturn, you know? If the official said it was a completion, that would have been ruled a completion. Instead he called it an incompletion and we’ve got to live with it.”

Two plays later, on third-and-10, Newton dropped back to pass. Linebacker Von Miller, the game’s Most Valuable Player, hit Newton from the front, pulling the ball from Newton’s grasp as he fell backward. The ball skittered on the grass to the goal line. Defensive end Malik Jackson dived on it for a Denver touchdown. The subsequent extra point gave the Broncos a 10-0 lead.

“That’s the unfortunate part,” Rivera said. “That’s the cause and effect.”

There was no controversy over the sack and fumble recovery. But debate lingered over what looked like a 23-yard catch that was called an incomplete pass.

“No catch,” Stewart said after the game. “Because the ball clearly hit the ground when it was under him.”

He admitted he had not seen a replay.

Set amid the biggest game of the season, the call sparked the latest debate over what constitutes a catch — and why a play that has been part of professional football since 1906, when the forward pass was adopted, seems harder than ever to decipher.

Generally, the league puts catches into two categories.

If a receiver takes possession and appears to be a runner, able to ward off tacklers and make other moves, it is a catch; losing possession after that point represents a fumble.

If, however, the receiver grabs the ball and immediately falls, the rule essentially states that he needs to retain possession until he comes to a complete stop, even if that stop occurs well out of bounds or in the end zone.

In the case of Cotchery, it was difficult to tell which rule applied. Cotchery had hold of the ball and was pulled down in one motion. He was running, but perhaps had not become a runner by the NFL’s definition — a layer of subjective analysis used to help determine the subjective call of whether a catch is made.

And while the ball appeared to move in his grasp as Cotchery fell, slow-motion replay showed that his left hand stayed below the ball, protecting it from hitting the turf. Replay ultimately provided no help, however, despite the time consumed and the angles evaluated.

The ruling on the field stood. Newton fell, two plays later. And the game went on, leaving questions behind.