McCaffrey (thigh) went to the locker room during Sunday's game in Atlanta, Harrison Rich of the San Francisco Chronicle reports.
McCaffrey remained on the sideline for the 49ers' third possession to get his left leg worked on, which seemingly stemmed from a hit he took on a 24-yard catch on the team's first drive. Officially questionable to return due to a thigh injury, he attempted to warm up on San Francisco's bench before jogging to the locker room in the middle of the second quarter. Kaelon Black will be the team's leading runner for as long as McCaffrey is out of the contest.