KANSAS CITY, Mo. -- The Kansas City Chiefs secured the week seven win in San Francisco, but yet another costly injury could see them without a starting cornerback after a left ankle injury on Sunday. Jaylen Watson suffered the injury early in the fourth quarter and limped off the field. Head coach Andy Reid didn't give an encouraging response regarding the status of Watson after the game. End Zone Extra: Get the top Chiefs news and insider features all season long "We'll see what the MRI says, but I don't think that's going to be great news," Reid said. Watson earned the starting second DB spot in the preseason and has played well this season. Nazeeh Johnson filled in for Watson when he went down, Johnson had a holding penalty and gave up a 41-yard reception to 49ers WR Jacob Cowing in limited action. However, Johnson did have a good training camp and preseason and will likely be the starter next week in Watson's absence. According to the The Athletic's Nate Taylor, Watson was on crutches and with his left ankle and foot in a cast after the game. Patrick Mahomes releases shoe honoring Negro Leagues Baseball Museum On the season, he has 19 tackles and six pass deflections in six games. The Chiefs will stay on the West Coast when they face the Las Vegas Raiders next Sunday at 3:25 p.m.