Tyrell Williams raised his hands in triumph without even needing to look.
He knew the second both Orlando Scandrick and Kendall Fuller went to him on the two-point play that Mike Williams would be wide open.
Sure enough, he watched with arms extended high in the air as Philip Rivers' pass floated into the waiting hands of Mike Williams.
Pandemonium ensued.
After trailing by 14 late in the fourth quarter, the Chargers took their first lead of the game with four seconds left.
So, just how did Mike Williams get that wide open?
Let's let the coaches and players explain it themselves.
According to Philip Rivers, two players immediately came to mind to feature - Antonio Gates and Mike Williams.
"What do we want?" Rivers asked rhetorically. "Mike was rolling. In those situations, it's the guy that's caught more touchdowns than any tight end ever in football, and Mike Williams, who's on fire. So, let's give these two guys a shot and win or lose with them right there. So, we had Gates running the back line and Mike running what he ran, and one of them is going to get a shot."
Rivers outlined how the play was identical to the team's first touchdown strike. They just changed some things around pre-snap that confused the Chiefs.
"They busted (coverage)," Rivers explained. "We had Travis (Benjamin) over there with (Mike). We motioned Travis and so then we had to communicate that they're playing man coverage, and then had to communicate that they had two coming out and one coming in. It was the same play we ran when Mike had his first touchdown. We just dressed it up a bit."
As Russell Okung later explained, it was a beautiful play design by Offensive Coordinator Ken Whisenhunt, who is one of the best in the business when it comes to drawing them up.
"When you have a great offensive coordinator in Ken Whisenhunt and a head coach (in Anthony Lynn) that gives these guys the freedom to do what they do and to dial it up the right way. I am not surprised that Mike Williams is over there wide open," he said. "He is that sort of guy."
Meanwhile, Tyrell Williams was the first person to know it was going to be converted.
As soon as he broke in, and felt both corners break on him, it was game over.
"Once I went in, I knew they both came with me," he explained. "I didn't even look back. I knew it was going to be a wrap, so it's a good feeling…. It's the best. All I can (say) is when they both came on me, I knew it was game over, so I started celebrating before he even caught (it) but it's just exciting, man, it's exciting."
While Tyrell Williams knew it right away, Mike Williams realized it a fraction of a second later.
"They left me wide open," he said. "The dude who was in front me, they both went with Tyrell. Phil threw it up, I just made a play.… I had the out route, he had the in route. I guess they had busted coverage and they left me wide open in the back of the end zone. I held my hand up before I even caught the ball. I knew it was a two-point conversion. I knew it was good. I just wanted to go celebrate with my teammates."