Seahawks linebackers Bobby Wagner goes airborne to block the Vikings’ Dan Bailey’s field goal attempt Monday night. (Stephen Brashear/Associated Press)

Bobby Wagner made one of the key plays in Seattle’s 21-7 win over the Minnesota Vikings Monday night when the standout linebacker leaped over the line of scrimmage to block a fourth-quarter field goal attempt by kicker Dan Bailey.

The problem was that the play was not legal and should have been penalized, although perhaps not for the reason many observers probably thought.

Last year, at the urging of the NFL Players Association, the league banned leaping over the line of scrimmage to try to block field goal or extra point attempts. It was billed as a player-safety measure designed to protect the player doing the leaping as well as the blockers on the kicking team. Previously, it had been a legal tactic if the player cleared the line of scrimmage, but illegal if he landed on anyone.

However, that was not what was wrong with Wagner’s leap. Wagner did not get a running start, having originally been lined up in a stationary position at the line of scrimmage. Under the rule, it is only a penalty for a player to take a running start and then leap over the line to attempt to block the kick.

What Wagner did that was against the rules was place his hands on two teammates lined up alongside him as he made his jump over the line. Under NFL rules, it is illegal to place “a hand or hands on a teammate or opponent to gain additional height to block or attempt to block an opponent’s kick or apparent kick, or in an attempt to jump through a gap to block an opponent’s kick or apparent kick.”

There was some debate after the game over whether Wagner actually propelled himself over the line by using his teammates as leverage. But several former NFL referees posted to social media that a penalty should have been called.

“Clearly a foul by Seattle on the blocked FG,” former referee Terry McAulay, now a rules analyst for NBC, wrote on Twitter. “A player cannot use his hand[s] on an opponent or a teammate to jump through a gap to block a FG.”

Gene Steratore, the former NFL referee who now is a rules analyst for CBS, wrote on Twitter: “As many have noted, the play … should have been a penalty on Seattle for leverage. The officials should not have picked up the flag on that play.”

Mike Pereira, the former NFL vice president of officiating who is a rules analyst for Fox, tweeted: “Lots of talk about the Wagner block. The wording in the rule book is NEW this year and is clear. The new wording states, ‘May not place a hand or hands on a teammate or opponent in an attempt to jump through a gap to block an opponent’s kick or apparent kick.’ Case closed. Foul.”

Officials threw a flag but opted against enforcing a penalty. The blocked 47-yard kick came at a key moment in the game, with the Vikings trailing 6-0 with less than six minutes remaining. The 15-yard unsportsmanlike conduct penalty, if enforced, would have given the Vikings a first down at the Seattle 14-yard line.

Vikings Coach Mike Zimmer said after the game he hadn’t had a clear view of the play. He was told that he could not challenge the call via replay.

“You’re not supposed to be able to pull guys down, if that’s what they did,” Zimmer said at his postgame news conference.

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