Branch was hit in the back by Smith-Schuster during the fourth quarter of their matchup on Sunday. After the game ended, Branch approached Smith-Schuster and started a fight with him, leaving Smith-Schuster with a bloody nose.
Chiefs quarterback Patrick Mahomes tried saying good game to Branch after the final whistle.
But the safety ignored him and went right for Smith-Schuster.
Branch will miss the team's Monday night game against the Tampa Bay Buccaneers next week.
The Lions Pro Bowl safety admitted his fault and apologized after the game.
Smith-Schuster also commented following his team's 30-17 win, as they improved to 3-3 on the year.
The nine-year veteran finished the matchup with 57 receiving yards on three receptions.
Kansas City will face their division rival Las Vegas Raiders on Sunday, October 19th.