He wasn't even supposed to start in this game, but Kansas City Chiefs cornerback Jaylen Watson made a game-changing play against the Los Angeles Chargers on Thursday night. 

The Chargers were driving with tight end Gerald Everett having a catch-and-run that set up quarterback Justin Herbert for first-and-goal to try and take the lead, as the game was tied at 17 apiece.

Watson had another thing in mind on the very next play. 

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The Chargers were rushing up to the line of scrimmage to try and catch the Chiefs' defense off guard. It had the opposite effect, as Everett was calling to his sideline to come out of the game. Instead, he was the intended target on the next play and there seemed to be some miscommunication as he went outside, and the ball went inside. 

Watson caught it instead on the one-yard line and was off to the races. 

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The seventh-round pick from May danced around a couple tackles, including Herbert, and took it the distance for his first career Pick Six.

Watson was filling in for first-rounder Trent McDuffie, who couldn't play due to injury. In a moment where he had to step up against a potent Chargers offense, he made it count. 

The Chiefs went on to win, 27-24, with the pick-six changing the entire dynamic of the football game. 

Herbert finished the game a bit banged up after taking a hard hit on a pass attempt in the fourth quarter. He ended up playing through it and threw a touchdown to wide receiver Josh Palmer to pull within three points. 

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On the ensuing onside kick, the Chiefs bobbled the initial touch of the ball, but were able to recover to kneel out the rest of the game. 

Chiefs quarterback Patrick Mahomes finished with two touchdown passes and 235 yards through the air.