The NFL acknowledged a series of officiating mistakes in a wild sequence at the end of the first half of Monday night’s game in Seattle that perhaps cost the Buffalo Bills a field goal and, potentially, a late-game chance to tie the score.

The Seahawks’ Richard Sherman should have been called for unnecessary roughness on a play on which he plowed into Bills kicker Dan Carpenter after jumping offside on a field goal try.

“At the end of the half… it[’]s unnecessary roughness for hitting the kicker,” Dean Blandino, the NFL’s senior vice president of officiating, wrote on Twitter. “Foul means he can stay in the game.”

Later, in a postgame interview with the league-owned NFL Network, Blandino said: “The referee didn’t think that the contact was severe enough. He felt that players were coming together and he just didn’t think it was a foul. We looked at it. It is a foul. It’s no different than a defender coming offside and hitting the quarterback after the whistle blew. So it should have been unnecessary roughness.”

The officiating crew, led by referee Walt Anderson, called Sherman for being offside but did not assess a personal foul. Carpenter was ordered to leave the field for one play after receiving on-field medical attention.

Only three seconds were left in the half. The Bills were able to line up and spike the football to stop the clock with one second remaining. Carpenter, after sitting out a play as required, returned to the field and lined up in field goal formation again. He appeared to connect on a field goal, but the Bills were called for delay of game. That nullified the successful kick and pushed Buffalo back five yards. Carpenter then missed a 54-yard field goal try as the half ended.

However, replays showed that an official was standing over the football until only a few seconds remained on the play clock before the delay-of-game penalty. The officials did not reset the play clock.

Blandino told the NFL Network that the play clock should have been reset.

“There was a conversation on the field between a couple of officials,” he said. “And the umpire was actually over the ball. Any time the play clock goes down under 20 seconds, we want to reset it if we’re still over the football. And it looked like the play clock had run down probably to about five or six seconds. And so we want to reset the play clock there, when the officials are actually conversing and delaying the snap. That’s what happened there.”

Bills Coach Rex Ryan was livid at the officials at the time. He also was critical when asked during his postgame news conference about the sequence.

“Ridiculous,” Ryan said. “Absolutely ridiculous.”

Ryan was asked what explanation he’d gotten from the officials.

“That doesn’t matter,” Ryan said. “It was wrong. It’s clear what happened. Their guy roughed our kicker, jumps offsides, roughs our kicker. And then because we had to go out and attend to him and it wasn’t called roughing the kicker, then we had to spike the ball so he can come back in and kick. He needed a little time there…. And then, of course, they’ve got to put the [kicking] ball out there and they don’t reset the clock. So from an officiating standpoint, I think you can do a little better than that.”

The Bills lost to the Seahawks, 31-25. They failed on a fourth-and-goal play from the Seattle 15-yard line in the game’s final seconds, with quarterback Tyrod Taylor throwing incomplete. It’s possible that if they’d gotten a field goal at the end of the first half, they could have kicked a tying field goal then and sent the game into overtime.

“Yeah, of course,” Ryan said when asked about that scenario. “We had all the momentum. We were outplaying them. That was clear.”

Blandino said the first-half mistakes would be addressed with the night’s officiating crew.

“We’re absolutely gonna address it,” he said. “Any time you have a sequence like that at any point during the game, we want to see what happened and just walk through the steps of where the breakdown was. And so regardless of the outcome of the game, we’re gonna address the situation with our crew.”