The Cowboys didn't have Ezekiel Elliott on Saturday night, but most of the team's other offensive starters, aside from Jason Witten, took the field for a series in the preseason opener.
Dak Prescott led the Cowboys on a nine-play, 69-yard scoring drive before leaving for the night. It ended in a 25-yard field goal by Brett Maher with 10:30 remaining in the first quarter.
Prescott went 4-for-4 for 23 yards, completing passes to Michael Gallup (two catches, 19 yards), Tavon Austin (one catch, 5 yards) and himself on a batted pass (one catch, minus-1 yard).
The Cowboys, though, could not punch it in after having a first down at the 49ers' 12-yard line. The red zone is an emphasis for the Cowboys this season after they finished 29th in red zone efficiency last season, getting 24 touchdowns and 16 field goals in 50 red-zone chances.
Cooper Rush, who is competing with Mike White for the No. 2 job, replaced Prescott. He went 3-for-5 for 59 yards on his first drive, leading the Cowboys to a second field goal.
Maher, who has been shaky in camp, made a 40-yarder with 4:04 remaining in the first quarter to give Dallas a 6-0 lead over the 49ers.
Rookie Tony Pollard started for Elliott, who is holding out. He had four carries for 16 yards on the Cowboys' opening drive.