The San Francisco 49ers signed veteran quarterback Nate Sudfeld on Tuesday, a move revealed to be necessary once practice began. Brock Purdy's primary backup, Mac Jones, was absent from the team's first practice of the week ahead of their preseason finale against the Los Angeles Chargers.
NBC Sports Bay Area's Matt Maiocco reported that Jones appeared to suffer a knee injury during Saturday's preseason matchup against the Las Vegas Raiders. Fortunately for the 49ers, the injury is not believed to be serious.
49ers backup QB Mac Jones is not at practice. He appeared to sustain a knee injury on Saturday. It's not believed to be too serious, but it explains the signing of Nate Sudfeld. Kyle Shanahan will update after practice.
— Matt Maiocco (@MaioccoNBCS) August 19, 2025
#49ers QB Mac Jones was injured late in second quarter Saturday on this play. #49ers pic.twitter.com/OlhaEWWzrf
— Eric Branch (@Eric_Branch) August 19, 2025
San Francisco signed Jones to a two-year deal in March, aiming to solidify the quarterback depth chart behind Purdy. Against the Raiders, the 26-year-old completed 13 of 16 passes for 135 yards, with one interception and no touchdowns.
Jones, a former first-round pick (No. 15 overall) by the New England Patriots in 2021, is entering his fifth NFL season. He previously played for the Patriots and the Jacksonville Jaguars before landing with the 49ers.