Mullens completed 11 of 17 pass attempts for 105 yards, a touchdown and an interception in Saturday's preseason win over the Cowboys.
Mullens is jockeying for position with C.J. Beathard to be Jimmy Garoppolo's primary backup this season. The fact that the 24-year-old started Saturday's contest gives him the early advantage over Beathard in the job competition. Both signal callers had very similar stat lines, so this battle could go down to the wire.