In the run-up to playing the Steelers, 49ers coaches said they were encouraged by the progress Jarryd Hayne has made at running back. But when starter Carlos Hyde left the game following a blow to the head, it was Mike Davis, not Hayne, who received all of the carries.
While Hayne was the first running back off the bench, he played only four offensive snaps Sunday, all of them in the first half. Davis was on the field for 41 snaps.
Reggie Bush hinted at that arrangement last week when he noted that, as expected, Davis was better than Hayne when it came to pass protection. Davis, after all, has been playing football all of his life. Hayne only began playing American football this year.
"He's obviously better at it than Jarryd because he played football longer, he has more experience at it," Bush said of Davis. "But Jarryd's doing well also. He's coming along."
Bush did not make the trip to Pittsburgh because of a calf strain suffered in Week 1. Hyde, meanwhile, played until the middle of the third quarter on Sunday at which point the crown of his helmet struck linebacker Lawrence Timmons'. He passed all of the concussion tests and said he was cleared to go back in the game.
Neither Davis nor Hayne was very effective. Davis finished with 14 yards on seven carries as well as two catches for four yards. Hayne had three yards on two carries
Bush told The Bee on Friday that he planned to be back for the upcoming game against Arizona.
* Despite the lopsided score, the 49ers defense only played 57 snaps. That's because the Steelers scored their touchdowns so quickly. San Francisco held the ball for nearly 14 more minutes and had several long drives. However, they scored a touchdown on only one of four trips to the red zone. The 49ers offense had 90 snaps.
* Fullback Bruce Miller played only 14 snaps. Instead the 49ers again leaned on a three-tight end formation, even after Vance McDonald left the game with a knee injury. Rookie Blake Bell played 18 offensive snaps after playing just one snap vs. Minnesota. An ankle injury to Bruce Ellington allowed DeAndrew White to play 16 snaps. He had two catches for 18 yards.
* Rookie safety Jaquiski Tartt played 11 snaps after playing 20 vs. the run-heavy Vikings. Fellow safety Jimmie Ward played 27 snaps against the Steelers after getting 13 snaps against the Vikings.
* Nose tackle Ian Williams played 40 snaps after playing 36 against Minnesota.
* First-round draft pick Arik Armstead played 14 snaps; third-round pick Eli Harold played eight.
* Blaine Gabbert, Ian Silberman and Trent Brown were listed as not having played.