Mustapha registered three tackles (two solo) and one pass defense during San Francisco's 42-38 win over Chicago on Sunday.
Mustapha played every single defensive snap during Sunday's win, but his three tackles were his lowest since Week 6 against the Buccaneers (two). The second-year safety is up to 71 combined tackles across 11 regular-season games, which is one stop shy from matching his total from his rookie campaign across 16 regular-season games. Mustapha should surpass that mark during the 49ers' Week 18 tilt against the Seahawks on Saturday, a game that will determine who captures the NFC West and enters the postseason as the No. 1 seed in the conference.