James Palmer of NFL Network reported Watkins was running at full speed before being ruled out last week.
In his first season with the Chiefs, Watkins has dealt with periodic injuries. He previously missed a game in 2018 because of a hamstring injury but has been effective when in the lineup. The 2014 first-round pick has compiled 39 receptions for 515 yards and three touchdowns this season.
"I'm happy for Sammy," Chiefs coach Andy Reid told reporters. "Sammy has gone through a few things through his career, and he comes here as one of the big names, he saw what he is. You get that ball in his hand, and he's an explosive runner. It's like you have a running back when he has that ball, big, strong and physical."
Watkins has missed at least one game in four of his five NFL seasons.
Tyreek Hill recorded seven receptions for 117 yards and two touchdowns with Watkins out of the lineup last week versus the Arizona Cardinals. Demarcus Robinson had three catches for 30 yards in an expanded role.