What happened: Kyle Shanahan ruled out Mike Evans on Friday for Sunday's game at Atlanta. Evans has missed practice for two straight weeks with an Achilles issue, which he aggravated against Washington before leaving that game before halftime. Christian Kirk practiced fully all three days this week and is expected to make his 49ers debut. Kirk hurt his calf on the first day of training camp, and Shanahan called his questionable tag procedural.

Why it matters: The 49ers are 6-0 and go for 7-0 against a 2-4 Falcons team that has lost two straight. They will also be without Deebo Samuel, Demarcus Robinson, De'Zhaun Stribling and Ricky Pearsall, who had season-ending PCL surgery. Six players who are not on injured reserve have been ruled out, so San Francisco could dress fewer than 48 players, and third-string quarterback Kurtis Rourke is in line to serve as an emergency receiver. Until Kirk is activated, Brandin Cooks is the only healthy wideout on the active roster with more than 10 career catches.

What to watch: San Francisco released Ogbo Okoronkwo to open a roster spot for Kirk and is expected to re-sign him to the practice squad. With Kirk's activation pending, more targets are likely to go to George Kittle, Christian McCaffrey, Jordan Watkins and Jacob Cowing.