Foster, who missed last week's game against the Washington Redskins, has practiced the entire week and head coach Kyle Shanahan was optimistic the linebacker would play on Sunday.
"He's not 100-percent ready to go but I feel very optimistic about it," Shanahan told reporters on Friday. "He had another good practice today. As long as there's not any setbacks here over the next 40 hours or whatever it is, I feel pretty confident."
Not only will Foster play against Dallas, but he will reportedly start. He practiced last week as well but was among the inactive players against Washington.
Foster will likely take over the Mike linebacker spot vacated by the departure of NaVorro Bowman. Brock Coyle filled that role against Washington. Ray-Ray Armstrong will likely play at the weak-side linebacker spot.