49ers running out of RBs with Packers coming to town

Through two games, the San Francisco 49ers have two wins and perhaps the same number of healthy running backs on their roster.

That could create a real issue for them going into their home opener Sunday against the Green Bay Packers in Santa Clara, Calif.

After losing starter Raheem Mostert to a season-ending knee injury during its opener at Detroit, San Francisco then saw JaMycal Hasty go down with a high ankle sprain in last week’s 17-11 win at Philadelphia. Hasty is likely to wind up on short-term injured reserve, which would require him to miss at least three weeks.

What’s more, rookies Elijah Mitchell (shoulder) and Trey Sermon (head) were also dinged up last week. Coach Kyle Shanahan said Mitchell is day-to-day, while Sermon is in concussion protocol but could play Sunday.

In addition to all that, last year’s leading rusher, Jeff Wilson, isn’t expected back until November after suffering a meniscus tear in the offseason. There’s a good chance the 49ers’ running back depth chart will consist of Trenton Cannon and Jacques Patrick, who between them have one carry — Cannon’s 1-yard loss last week in Philadelphia.

Former Lions running back Kerryon Johnson is on the team’s practice squad and could be a possibility to play this week. And San Francisco on Wednesday signed eight-year veteran Chris Thompson, who has 1,214 yards in part-time duty with Washington and Jacksonville.

But despite all their injuries at running back, San Francisco is still a 3 1/2-point favorite over the Aaron Rodgers-led Packers. The reasons? A solid defense that is 10th in the NFL in points allowed, and the fact that quarterback Jimmy Garoppolo is rising to the challenge provided by rookie Trey Lance.

While fans and some media pundits have demanded Shanahan insert Lance into the lineup, Garoppolo is completing 70.9 percent of his passes for 503 yards and no interceptions. He’s found a new favorite target in Deebo Samuel, who has 15 catches for 282 yards.

“You don’t really make decisions based off your team of just putting a guy in totally just for how that is for him in the future,” Shanahan said of playing Garoppolo. “I think that’d be irresponsible to everybody else in the room.”

That’s not a question across the field.

Rodgers bounced back from a rough outing in a 38-3 season-opening loss to New Orleans with a stat line more characteristic of his career on Monday night, going 22 of 27 for 255 yards and four touchdowns in a 35-17 defeat of Detroit.

While Green Bay’s defense remains a source of concern, even though it held the Lions scoreless in the second half, Rodgers looked as efficient as ever. He leaned on Davante Adams for his standard 8-catch, 121-yard effort, but also spread the wealth among Robert Tonyan, Aaron Jones and Randall Cobb.

Jones caught three short scoring strikes Monday night and added a fourth touchdown on the ground, lending the team the balance it enjoyed during last season’s run to the NFC Championship Game.

Yet Rodgers wasn’t completely satisfied, citing a couple of plays on which he failed to connect with Marquez Valdes-Scantling and Allen Lazard. Of course, the time he missed Lazard just happened to be the play he found Tonyan for a go-ahead 22-yard score.

“He is the ultimate competitor and he wants everything to be perfect,” Packers coach Matt Lafleur said. “He puts a lot of pressure on himself for him to make it perfect.”

Rodgers’ task might be tougher if left tackle Elgton Jenkins (ankle) is sidelined. Jenkins missed practice on Wednesday after playing all 65 plays Monday night.