Isaac Guerendo

Mason is limited/questionable player who seems to be genuinely questionable. He looked like he was going to play through his shoulder ailment last Thursday evening before checking back out after only one snap. The Niners could ultimately decide he's at too much re-injury risk to build a game plan around his rushing in their Super Bowl rematch with the Chiefs. Isaac Guerendo lies in wait ahead of Friday's all-important injury report update.

49ers RB Jordan Mason (shoulder) was limited in Wednesday's practice. HC Kyle Shanahan previously labeled Mason "day to day" with his sprained AC joint. He seems legitimately questionable for Sunday's showdown with the Chiefs. We'll keep you updated on Mason's status leading up to that one. His absence would leave rookie Isaac Guerendo as San Francisco's lead back against the league's top-ranked RB defense.

Deebo Samuel and Isaac Guerendo helped the 49ers make NFL history in San Francisco's 36-24 win over the Seattle Seahawks last week.

Did rookie running back Isaac Guerendo intentional go down before reaching the end zone on a 76-yard run late in the 49ers' win? No one in San Francisco's locker room can agree.

The "day-to-day" designation is the best-case scenario for Mason, who went down with the shoulder injury on Thursday Night Football versus Seattle. He attempted to play through the injury, but San Francisco gave him one second-half carry before putting him on ice for the remainder of the game. With a long turnaround until San Francisco's Week 8 matchup with Kansas City, Mason may be able to return without missing any time. Rookie running back Isaac Guerendo should still be stashed in all formats.