49ers backups get chance to shine in 2nd preseason game

HOUSTON - Not as much is riding on Friday's visit to NRG Stadium as last December's for the 49ers.

Remember that one? Jimmy Garoppolo does.

After winning and improving to 2-0 as the 49ers' starter, he coyly said he didn't know if that meant he earned a shot at going 3-0. “This is only my second start, so I'm gaining trust in guys, and they're gaining trust in me,” Garoppolo said. “It's going in the right direction.”

Right direction, indeed. The 49ers and Garoppolo would win their final five games, and their 26-16 win in Houston also saw breakout efforts from Garrett Celek, Kyle Juszczyk and Adrian Colbert.

Fast forward to this return visit and the 49ers aren't riddled with questions. Right guard remains the only starting job up for grabs. Most starters won't play more than a series or two, seeing how six players got hurt in last week's opener. Here are five areas worth exploring:

RUNNING BACK REPS: Unheralded Jeremy McNichols saw first-team reps in an interesting twist at this week's joint practices with the Texans. McNichols spent most of last season on the practice squad after the Tampa Bay Buccaneers released him, and he had only three carries (15 yards) in last week's exhibition opener.

Alfred Morris, who signed Tuesday to reunite with coach Kyle Shanahan, could play - but don't expect much action. Instead, this game and next week's exhibition at Indianapolis could be huge for Joe Williams' fate. As for Raheem Mostert, he had a team-high 57 rushing yards last week and the 49ers know how valuable a special-teams player he is, so there's not as much urgency for him to audition. Jeff Wilson also can share the workload as Jerick McKinnon (calf) and Matt Breida (shoulder) sit out until Week 1.

MISSING PIECE: Training camp is officially over but the 49ers are still debating who will start at right guard, and it looks as if Joshua Garnett and Jonathan Cooper could be cleared to play after missing last week's exhibition with knee concerns. Those two figure to duke it out for the starting job, but if their health problems persist, Mike Person has had the most first-string reps.

“We've got the competition going at right guard right now and it's pretty open,” left tackle Joe Staley said. “We've got a lot of guys that have opportunities to kind of make names for themselves and jump up here with the last couple preseason games. Mike's developing every single day.”

RATING RECEIVERS: Trent Taylor could make his exhibition debut, and whether or not he does, the 49ers need a better look at wide receivers who are on the bubble - which he's not. Nor is rookie Dante Pettis, who could see time just for experience. More intriguing is whether Richie James, Kendrick Bourne, Victor Bolden and Aldrick Robinson will build off their respectable outings last week.

BACKUP SAFETY: A year after tearing his anterior cruciate ligament, Chanceller James has a golden chance to lock down a backup role behind strong safety Jaquiski Tartt. Two other options got hurt practicing against the Texans: Terrence Williams Jr. went on injured reserve Friday (knee), and rookie Marcell Harris is likely out with a hamstring issue. Dexter McCoil was re-signed Friday, having played in eight games last year for the 49ers. Meanwhile, Eric Reid remains unemployed.

CORNERBACK JOBS: Teams never can have enough cornerbacks, and that's especially true for a 49ers team that likely won't unveil Richard Sherman (hamstring, Achilles) until the game at Minnesota in Week 1. So, with Jimmie Ward and Ahkello Witherspoon the exhibition-season starters, and with D.J. Reed filling in at nickel back for K'Waun Williams (ankle), the 49ers can take a better look at Greg Mabin, Tyvis Powell and rookies Tavarius Moore and Tarvarius McFadden.