Vick was the third quarterback against Tennessee as he recovered from injured rib cartilage.
"It's Mike," Reid said.
Vick said in the locker room that he wouldn't know until he got hit whether he was 100 percent or not, but his ribs felt good.
"I've got some time to heal, some more time to get stronger. If they really needed me down the line, I probably could have (played)," Vick said. "If Kevin or Mike (Kafka) would have went down, I could have gotten through."
Vick understands the challenges that come with being No. 1 on the depth chart.
"It's a huge responsibility, anytime you're a starting quarterback in the NFL," Vick told NFL Network's Albert Breer. "The thing is, you have to make sure you're being held accountable and doing all the things it takes to win football game. You know, it's a tough league and every week it's gonna be a challenge."
Kolb began the season as the Eagles' starter after they traded away Donovan McNabb. But he suffered a concussion in the opener and Vick played so well in his place that he remained the starter when Kolb returned.
Then Vick, the NFC's top-rated passer at 108.8, got hurt himself Oct. 3 in a loss to Washington.
Kolb, the NFC's second-rated passer coming into Sunday, started at San Francisco and at home against Atlanta. The Eagles won both games, and Kolb was named NFC offensive player of the week after throwing for 326 yards in the win over Atlanta.
Vick said that his friendship with Kolb keeps the situation from becoming an uncomfortable or negative one.
"It's helped both of us because we can compete and be friends at the same time, and it's not like you're competing against a guy you don't have a relationship with or can't talk to, that puts more pressure on the situation," Vick told Breer. "Naturally, we developed a friendship -- we like fishing, we like a lot of the same things, we roomed together in camp and we had a great offseason together. We're just rooting for one another."
But Kolb was 26 of 48 against Tennessee. His first interception came a play after safety Quintin Mikell stripped Titans quarterback Kerry Collins of the ball in the second quarter. He lost the fumble at the Titans 3 in the third quarter, and he was intercepted to end the game. That was returned 41 yards for a touchdown as time expired.
Reid said Kolb was up and down Sunday.
"He had some good plays, phenomenal plays," Reid said. "We've got to continue to work with the pressure and make sure that we protect him. We've got to make sure we give him the right plays."
"I enjoy playing out there, and I want to continue to play. But, I'll say it again, I always trust him (Reid). And I trust him now," Kolb said.
The Associated Press contributed to this report.