Mostert, a fifth-year running back who was often buried on depth charts, has six carries for 60 yards and a touchdown during the first half of play. He also has a 35-yard touchdown reception, caught on a pass, not from quarterback Jimmy Garoppolo, but wide receiver Emmanuel Sanders.
The 49ers currently lead the Saints 28-27. San Francisco took its first lead of the game thanks to Mostert's 10-yard scoring run near the end of the first half.
Running back Matt Breida, who was inactive the last three games due to an ankle injury, returned but has just one carry. It did go for a 28-yard gain, however.
Mostert now has 599 yards rushing through 12 games this season. He is averaging 8.1 yards per carry over the last three games, including the first half of this shootout in New Orleans.