Vick was forced off the field due to a hamstring injury during the second quarter of his side's match against the New York Giants yesterday, with Foles replacing him before throwing two fourth-quarter touchdown passes to seal a 36-21 victory for his side.
Kelly confirmed that Vick would start next weekend's match against the Tampa Bay Buccaneers if he is fit, but hinted that the door was open for Foles to challenge him for the starting spot.
"We're always going to compete and make sure the best guys are on the field," Kelly told reporters. "[Vick] wasn't 100%.
"He didn't look like he was moving well. He didn't have that step to get out of the way. I have a lot of confidence in Nick.
"If Nick were to go down, I think Mike could have gone back in. You'd better have two quarterbacks in this league."
The win halted a run of three consecutive defeats for the Eagles, improving their overall season record to 2-3.