Broncos vs. 49ers live updates, score: All-Pro CB Patrick Surtain II exits with apparent non-contact injury

The San Francisco 49ers host the Denver Broncos on Sunday afternoon in Week 4, as Kyle Shanahan & Co. look to maintain their perfect record at Levi's Stadium. They've outscored opponents 71-43 over three games, with quarterback Brock Purdy looking like an MVP to this point in the season, though Denver's defense may just mark his biggest challenge yet. The team did get some good news, as starting wide receiver Mike Evans is officially active after suffering a rib injury last week. The Broncos have seemingly bounced back from a brutal Week 1 loss against the Kansas City Chiefs, now coming off consecutive wins and looking to stack a third in Week 4. Bo Nix has been off to a relatively slow start this season despite two game-winning drives, averaging just over 200 passing yards per game with four touchdowns and three interceptions this year, but he catches a big break facing San Francisco's defense, which remains without Nick Bosa as he works through a calf injury.Where to watch Broncos-49ers in Week 4Broncos-49ers start time: 4:25 p.m. ETLocation: Levi's Stadium | Santa Clara, Ca.TV channel/live stream: CBSFollow along with Yahoo Sports for live updates, highlights and more as the San Francisco 49ers host the Denver Broncos in Week 4.