Delhomme sprained his right ankle in the season opener at Tampa Bay and has not practiced in two weeks. Backup Seneca Wallace started in last week's home loss against Kansas City and likely will face the Ravens if Delhomme doesn't make significant improvement in the next two days.
Mangini wouldn't say if Delhomme would be inactive for the second straight week.
"I don't know," Mangini said Friday before practice. "He's very aggressive with his rehab. It's like everything else he does, he does it very aggressively and each day it gets a little better. I have total confidence to operate the plan if he is available. We'll just have to see if he's available."
Wallace has made 16 career starts in eight seasons, but the mobile quarterback has never played against the Ravens.
Delhomme still is wearing a protective boot for walking. Mangini is confident the 35-year-old veteran could run the game plan without practicing.
Running back Jerome Harrison didn't practice again because of a thigh injury, increasing the likelihood James Davis will get his first significant action this season. Davis, a sixth-round pick in 2009, played in just two games as a rookie before being placed on injured reserve with a shoulder injury.
Tight end Evan Moore was cleared to practice after missing two days with a concussion sustained Sunday against the Chiefs.