Even better, the Bears expect to have two healthy running backs on Sunday, both of whom have 100-yard rushing games this season.
The obviously flexible Benson has a sprained medical collateral ligament (MCL) in his right knee and will be out about a month.
"Right now, it's week to week," Bears coach Lovie Smith said. "Hopefully we'll get him back before long. We don't know exactly how long it will be, but we know that we'll get him back sometime this year."
In other words, about a month.
Before he went down, Benson showed progress for the third straight week, reaffirming the Bears' belief that he will be the franchise back that they anticipated when they made him the fourth overall pick in the draft. He had 50 yards on 12 carries for a 4.2-yard average.
"Cedric Benson was having a real good game before he went down with the injury," Smith said. "Each time he plays we get a chance to see more and more what he'll be someday for us."
Starting running back Thomas Jones, who was held out last Sunday because of bruised ribs, is expected to be back in the lineup this week and might be at a Wednesday practice for the first time in more than a month.
The healthiest runner of the bunch is third-stringer Adrian Peterson, who stepped into the running back void last Sunday and produced 120 rushing yards, more than in any of his previous three NFL seasons.
Peterson has rushed for 205 yards this year, 15 more than in his first three seasons combined. He also leads the Bears with a 5.7-yard average and is one of the top special-teams players.
"He's stepped up all year," Bears offensive coordinator Ron Turner said. "He's a great football player, great on special teams, and whatever we've asked him to do, he's always stepped up and always been successful. This entire team has a lot of respect for him and what he can do, and he showed that again (Sunday)."
Peterson will probably be the only tailback behind Jones this week, although fullback Jason McKie can play that position in a pinch.
"Adrian Peterson just continues to play well every time we give him an opportunity," Smith said. "He had a lot of big plays (Sunday)."
--QB Kyle Orton had a season-low 67 passing yards, but he threw just 13 passes in 47-mph winds, completing eight, and easily outperformed the 49ers' Cody Pickett.
--QB Rex Grossman is running slowly and straight ahead, and throwing with good velocity on the side. But here's no way he'll be ready to return by his target date of Nov. 27. When he does return, he'll be in the mix behind rookie Kyle Orton, according to coach Lovie Smith.
--RB Thomas Jones is expected to start Sunday after resting his bruised ribs for a week. Jones might be healthy enough this week for his largest dose of practice time in the past month.
--RB Cedric Benson will be out about a month with a sprained MCL in his right knee. Benson had 164 yards on 29 carries this season leading up to his injury, an average of 5.7 yards per attempt. He had 50 yards on 12 rushes Sunday before he was injured.
--RB Adrian Peterson turned in the best performance of his four-year career for the second straight week with 120 yards on 24 carries. In the past two weeks, he has 178 yards on 30 carries, a 6.0-yard average.
--WR Muhsin Muhammad had just one catch for 3 yards in the 47-mph winds at Soldier Field on Sunday, but he drew a 23-yard pass interference penalty that helped set up the Bears' only offensive touchdown.
--WR Justin Gage had one catch for 6 yards in Sunday's windy conditions that made throwing the ball nearly impossible. His last five catches have netted just 34 yards.
--WR Bobby Wade had one catch for 11 yards and fumbled four punt returns, losing the ball three times. Coach Lovie Smith said Wade will keep the punt return job for now, but that could change soon.
--TE Desmond Clark was the Bears' leading receiver Sunday with 43 yards on two catches. The Bears' other receivers had a combined 24 yards.
--PK Robbie Gould missed a 39-yard attempt that appeared to make a 90-degree turn in mid-flight due to 47-mph winds. Gould connected on a 37-yarder and is 7-for-11 on the season.
--CB Nate Vasher returned a missed field goal 108 yards, the longest return of any kind in NFL history. Though he's a starting corner, Vasher could replace inconsistent Bobby Wade as the team's punt returner.
--SS Mike Brown picked off his third pass of the season.
--DE Adewale Ogunleye had four tackles for no gain or negative yardage against the 49ers.