Rarely does Patrick Mahomes lose his temper, but emotions boiled over for the Chiefs star at the end of Kansas City’s loss to the Bills on Sunday.

Minutes after what would have been a go-ahead touchdown was erased by an offsides penalty against Kadarius Toney, cameras captured Mahomes yelling in frustration on the sideline.

The Chiefs haven’t faced much adversity over the last few seasons, at least in comparison to most other franchises, but the last seven weeks have been an unusually challenging stretch for Kansas City. The Chiefs have lost four of their last six games, falling twice at home, and they now sit two games behind the Ravens in the race for the AFC’s top seed.

MORE: Kadarius Toney offsides penalty, explained

Even in wins, the Chiefs’ offense hasn’t been nearly as efficient as it was during last year’s championship season. Kansas City needs a spark ahead of the stretch run, and it’s possible a rare show of outrage from Mahomes could provide one.

Here’s what you need to know about who was on the receiving end of Mahomes’ outburst on Sunday.

Who was Patrick Mahomes yelling at?

While no one could blame Mahomes for being frustrated with mistakes by his wide receivers, he was actually directing his ire toward the officials for making the call against Toney.

After the game, Mahomes ripped into the officiating crew and called back to last week’s controversial finish in Green Bay.

“It’s tough to swallow. Not only for me, and football in general, to take away greatness like that, for a guy like Travis to make a play like that, you want to see the guys on the field decide the game,” Mahomes told reporters following the loss.

“I’ve never had offensive offsides called,” Mahomes said. “If it does, they warn you. There wasn’t a warning the entire game. And then you make a call like that in the final minute? Another game, we’re talking about the refs. It’s not what we want for the NFL.”

The Chiefs’ loss to the Packers last Sunday was also marred by controversial officiating decisions, most notably a non-call when Kansas City believed WR Marquez Valdes-Scantling was interfered with on the team’s final drive.

Mahomes clearly still had that moment in mind this week, telling reporters, “Every week, we’re talking about something.”

“Let us play the game. Then whatever happens happens. … I saw the picture. He’s barely offsides. It didn’t affect the play at all. At all,” he continued.

MORE: What’s wrong with the Chiefs’ offense?

Toney was the receiver who ultimately scored the would-be touchdown, after hauling in a well-timed lateral pass from Travis Kelce. It quickly became clear the wild play was coming back.

Andy Reid press conference

Andy Reid was more forward about his frustrations, telling reporters it was “a bit embarasing for the National Football League for that to take place,” explaining that he “normally” receives a warning before that type of call is made.

Both Mahomes and Reid seemed to have more of a problem with the procedure than the call itself, with each explaining that officials don’t typically make an offsides call without first warning the team that a player is lining up offsides.

Ultimately, it’s tough to deny that Toney was lined up offsides, whether it impacted the play or not. Because the call was made, the Chiefs (8-5) now face an uphill climb to secure a first-round bye in the AFC.