Gurley is dealing with a thigh contusion that he suffered in a Week 5 loss to the Seattle Seahawks. Talib has a rib injury that he also suffered in that game.
When asked if Gurley would be a game-time decision, McVay said, "He's doubtful right now, so we'll have a little bit more clarity and it's really just kind of taking our time making that decision."
If Gurley cannot play, Malcolm Brown and Darrell Henderson, a third-round pick from Memphis, will replace him.
"Never want to see my dog hurt or nothing like that, but definitely got to go in and take advantage of my opportunity and just be ready to do my job," said Brown, who has rushed for 114 yards and two touchdowns on 26 carries this season.
Cornerback Troy Hill, who started seven game last season, will replace Talib.
"I always told myself that I had to be prepared because I have been in these situations before and I've learned from the past," said Hill,
As the Rams prepare for Sunday's game, they also are dealing with another round of wildfires that have broken out in Los Angeles County.
Ebukam declined to discuss the situation, saying that he did not want to distract from the team's preparation for the 49ers.
"Those fires, I could smell them when I was driving over here," McVay said. "This is now the third year in a row this stuff has happened. Obviously I'm newer to this area, but it's so unfortunate when you have to watch people go through that and it's affecting three of our players right now and hopefully it's something where they will be able to return to their homes with no damage done and guys get everything under control."
Last season, the Rams dealt with severe fires in throughout Los Angeles and Ventura counties that forced approximately 100 players, coaches and staff members to evacuate their homes.