Foster has been dealing with a hamstring injury, which caused him to miss the team's Week 3 loss to the Giants. He saw limited action in last week's win over Buffalo, rushing six yards on eight carries. The three-time Pro Bowler sat out eight games last season due to a back injury.
Johnson injured his ankle against the Bills, and missed two of three practices during the week.
“I’m fine, I was more scared than anything because I felt a pop, so I went in and got checked,” Johnson said after the Buffalo game.
In 12 seasons with the Texans, Johnson has caught 12,923 yards and 61 touchdowns, and holds Houston franchise records for career receptions and receiving yards.
Foster, who was signed by Houston as an undrafted free agent in 2009, has rushed for 5,310 yards and 46 touchdowns in his six years with the Texans.
Both the Cowboys and Texans are 3-1 on the season.
-- Alex Suskind