When asked what more Foles must prove to him, Kelly said, "He just needs to continue to play, just like everybody else on this team."
It would be difficult for Foles to play any better than he did Sunday against the Oakland Raiders. Foles finished 22 of 28 for 406 yards and the seven scores.
When Kelly reviewed the film, what stood out was the way Foles played on third-and-long situations. Foles finished 6 of 8 for 81 yards and a touchdown. One was a 19-yard pass to Jeff Maehl on third and 13 and another was a 17-yard pass to DeSean Jackson on third and 16.
"Those are difficult down-and-distances to convert, and I think that was really kind of the key, especially early, to keep us on the field and keep our offense going," Kelly said.
The disparity between the way Foles played against the Raiders and the way he played Oct. 20 against the Dallas Cowboys remains dumbfounding.
"I've seen him in practice, seen him getting better and better," Kelly said. "His preparation led him to that, just really spent a lot of time, did his due diligence."
It remains a small sample size for Kelly to evaluate. The coach has seen Foles play just 21/2 regular-season games in his system.
A third-round pick out of Arizona in 2012, Foles arrived in Philadelphia with the reputation of being an accurate quarterback. He occasionally had trouble with the deep ball last season, but Kelly said that has not been an issue since last spring. Foles connected on three passes of more than 45 yards against the Raiders, including touchdowns of 46 yards and 63 yards.
Foles does not have an interception this season. Kelly said the second-year quarterback is gaining an understanding of pro defenses.
"I don't think he's getting surprised by what he's getting," the coach said.
The one part of his game that is not a surprise to Kelly is Foles' resilience. Kelly repeatedly mentions this intangible, and it explains the way Foles rebounded from the Dallas debacle.
Kelly remembered the games he coached against Foles when Oregon played Arizona. The Ducks won each time, but Foles had big games.
"We hit the crap out of that kid every single play," Kelly said. "He completed a pass against us lefthanded for 13 yards. Had his helmet turned around sideways and got up and took the next snap. I've always said that I've always been a big fan of his. I've seen him play, and I've seen him play in critical games."
Yet Kelly still did not name Foles the starter after the preseason and he has not handed him the job despite a 2-1 record as a starter. Foles has helped the Eagles to three of their four wins.
So it's another week with uncertainty about what will happen when Vick returns. The team's medical staff told Kelly that Vick's initial injury would require 10-14 days for recovery, but Vick reinjured the hamstring in his first game 21 days later. Kelly would not set a time frame for Vick's recovery from his latest ailment.
"They tell me when he can go, when he can't go," Kelly said. "I can cross my fingers, I can be hopeful, I can be wishful. But when they say he can go, he can go."
Until that happens, Foles will continue to have opportunities to unseat Vick. He made the most of Sunday's opportunity, just as he did in an Oct. 13 win over Tampa Bay. That was followed by the Cowboys clunker. Kelly said he has never seen Foles play that way before and he hopes he never sees it again.
But he offered the Cowboys game as a reminder of why Foles should remain levelheaded after his historic performance.
"If he needs anything to think about, he should think about what happened in the last couple of weeks to him," Kelly said. "It can change in a week."