First-choice quarterback Michael Vick is expected to miss Sunday's match against the Oakland Raiders having aggravated a hamstring injury during their 15-7 defeat to the New York Giants at the weekend, while back-up Nick Foles is currently recovering from concussion.
Should Foles not return in time, then that would leave the Eagles with rookie Matt Barkley as the only healthy quarterback on the roster, while GJ Kinne is on the practice squad but was only signed last week.
"I wish I knew a lot more than I do know. I don't have the final answer right now," Kelly told reporters.
The Eagles are currently second in the NFC East with a 3-5 record.