The Kansas City Chiefs have promoted Patrick Mahomes II to backup quarterback behind Alex Smith.

Tyler Bray was dropped to No. 3.

Andy Reid said the move was one that Mahomes earned and not something the Chiefs would have done regardless of how he played.

"It's not because of Tyler's performance in the game," Reid said of Bray, who threw an interception in his first series Friday against the San Francisco 49ers. "I thought he actually did very well ... and Patrick did a nice job, too. It gives [Mahomes] an opportunity to step up and work with that second group and see what he can do there.

"It's not something [Tyler] didn't do. [Tyler] is playing well. But Patrick has also done a nice job. In order to step up with that group, Pat would have had to [make] progress."