The mood inside Arrowhead Stadium quickly went from jubilation to frustration on Sunday afternoon.
Down by three to the Buffalo Bills inside the final 90 seconds of regulation, the Kansas City Chiefs appeared to pull off one of the more incredible late-game touchdowns you'll ever see.
On a second-and-10 from Buffalo's 49, quarterback Patrick Mahomes completed a pass downfield to tight end Travis Kelce. After avoiding a few defenders, Kelce threw a cross-field lateral to wideout Kadarius Toney, who caught the ball around the 24-yard line and ran into the end zone untouched.
Get top local stories in Connecticut delivered to you every morning. Sign up for NBC Connecticut's News Headlines newsletter.
But the wild go-ahead score was called back due to an offsides penalty on Toney.
After the penalty, Mahomes recorded three consecutive incompletions, resulting in a game-sealing turnover on downs.
And the two-time NFL MVP then had to be held back by teammates as he yelled at an official on the sideline.
A heated Mahomes also slammed his helmet into the ground.
After Kansas City's 20-17 loss, Mahomes voiced his frustration over the call to reporters.
"Obviously it's tough to swallow, not only for me, but just for football in general," Mahomes said. "To take away greatness like that, for a guy like Travis to make a play like that, and who knows if we win? But I know as fans you want to see the guys on the field decide the game."
"It's the call, man, just in that moment," Mahomes said when asked what sparked his sideline outburst. "I've played seven years and never had offensive offsides called. That's elementary school, we talk about it, you point to the ref, do all that different type of stuff and it doesn't get called. And if it does, they warn you.
"There was no warning throughout the entire game and then you wait until there's a minute left in a game to make a call like that, it's tough. Loss for words, man. It's tough because regardless if we win or lose, just for it to end with another game where we're talking about the refs, it's just not what we want for any of the NFL."
Former NFL ref and current CBS rules analyst Gene Steratore said that officials are generally not supposed to be "overly technical" when officiating the line of scrimmage. But Steratore added that, in this case, Toney was "blatantly" lined up in the neutral zone.
The Chiefs were on the wrong end of a brutal no-call in last week's 27-19 loss to the Green Bay Packers. With under a minute remaining in the game, a seemingly obvious pass interference call on the Packers that would have set the Chiefs up inside Green Bay's 10-yard line went uncalled.
The Chiefs have now dropped two straight games, with their lead over the Denver Broncos for first place in the AFC West being trimmed to one game. Mahomes and Co. will look to get back in the win column when they visit the New England Patriots in Week 15.