Foles' collarbone was examined early Monday. While it is healing, Foles cannot be subject to football contact until the bone has completely healed.
"The bone is not healed," Kelly said. "He'll start throwing a little bit more, but he's out for right now. He's not cleared and will not play this week. Until he gets fully healed, he's not going to be able to play with it. We think he'll be able to throw a little more this week, but we can't have anyone near him with contact."
Foles fractured the collarbone on his left (non-throwing) side during the Eagles' Nov. 2 game in Houston. At the time, he had completed 186-of-311 passes for 2,163 yards. Foles threw 13 touchdown passes and 10 interceptions in his eight starts. The Eagles were 6-2 in those eight games.
Mark Sanchez replaced Foles early in the second quarter in Houston. Sanchez has completed 138-of-223 passes for 1,752 yards. Sanchez has thrown for 10 touchdowns and nine interceptions. In the six games Sanchez has started, the Eagles are 3-3.
Asked if he has gotten consistent enough quarterback play to win the past couple of games, Kelly replied, "I think so. I think overall, the entire team, there's been good and bad at every position. We have to be more consistent overall. Mark will be the first to tell you that. I think everybody will tell you that. When we're not successful, we own it."
Sanchez took responsibility for the loss to Dallas on Sunday night. He threw two interceptions in the second half after the Eagles had fought back from a 21-0 deficit to take a 24-21 lead.
"You can't turn the ball over," Sanchez said. "I can't commit two turnovers like that. I didn't play well enough to win, and that's why we lost. ... We have to take ownership of this thing, and it starts with the quarterback. I have to be a lot better."
Sanchez will get another chance Saturday at Washington.