DETROIT - Throughout training camp, the Eagles' coaches gushed about the progress Nolan Carroll entering his second season with the team. A competition for the starting cornerback between Carroll and second-round pick Eric Rowe never truly materialized. Carroll earned the role.

Now the job will go to Rowe opposite Byron Maxwell. Carroll suffered a broken right ankle Thursday in the second quarter of the Eagles' 45-14 loss to the Detroit Lions. The injury will end the season for the 28-year-old, who played 99 percent of the Eagles' defensive snaps before Thursday's game.

"Nolan was a big part of the fight of our defense," defensive coordinator Bill Davis said. "It's a big loss. He's a great man who works his tail off."

Carroll injured his ankle in run support. He needed to be carted off the field. The Eagles' sideline emptied while players and coaches, including Chip Kelly, offered support to Carroll.

But the game needed to be resumed, and the Eagles' season must continue. Carroll's injury will force Rowe into the starting lineup.

"Hey, we're going to see what the rookie is," Davis said.

The Lions challenged Rowe on his first play in the game. He allowed a 10-yard completion to Golden Tate on the play. The Eagles kept Rowe as the right cornerback, so there were times he matched up with Calvin Johnson. Rowe was in one-on-one coverage on Johnson when the Lions star caught a touchdown before the end of the second quarter. Rowe held his own in coverage on other plays, but it was about as difficult of an assignment as a rookie cornerback can find.

"At first it's kind of surreal, but as the plays kept going, I just looked at him as another guy," Rowe said. ". . . I don't mind matching up man-to-man with him. I can run with him. He's pretty strong, but I feel I'm pretty strong, too. Kind of held my ground. As the game went on, my technique and confidence went up."

Rowe finished with two tackles and one pass deflection.

The Eagles' pass rush did not help the defensive backs much on Thursday. The Eagles had only two sacks, and despite halftime adjustments to try to bring pressure, Lions quarterback Matthew Stafford was able to handle blitzes and adjust protections.

Rowe will become the first Eagles rookie to start as an outside cornerback since Allen Rossum in 1998. His first start will come against the New England Patriots and quarterback Tom Brady, who is not reticent to attack a weak link in a lineup.

For Carroll, the injury is devastating for more reasons than ending his season. He is in the final year of a two-year contract with the Eagles and is set to be a free agent this offseason. A strong season would have enhanced his value.

"It's rough," safety Malcolm Jenkins said. "I know how much he puts into this game. He's a real hard worker. I feel for him. I know how much he loves to be out there. Whenever you see someone who puts all that in . . . and it gets taken away from him, it's tough."