JaCorey Shepherd's rookie season is finished before it even started after an MRI exam revealed Monday that the promising cornerback tore the anterior cruciate ligament in his right knee.

With that diagnosis, the Eagles lost a player who left them intrigued on draft weekend and excited during the spring workouts. He was the first player to take snaps at nickel cornerback after the team dealt Brandon Boykin on the eve of training camp, and Shepherd had been the front-runner for the position.

The injury occurred Sunday during practice when Shepherd and Darren Sproles collided during a seven-on-seven drill. The Eagles do not tackle during training camp practices, so Carroll was giving Sproles a "thud" when his foot appeared to get caught in the turf. Shepherd collapsed to the ground - Sproles said he was hollering - and left the field on a cart.

Shepherd slipped to the sixth round during draft weekend because of a hamstring injury that weakened his pre-draft testing. But the Eagles were bullish about what they saw on film at Kansas, where Shepherd started 42 games and was an all-Big Twelve selection last season. Their confidence was reinforced in the spring, and coach Chip Kelly touted the team's depth as a reason for shipping Boykin to Pittsburgh.

Without Shepherd, the Eagles could look at Jaylen Watkins, E.J. Biggers, Randall Evans, and Denzel Rice at nickel. They could also move Byron Maxwell or Nolan Carroll to the slot when they go into the nickel formation, or even use safeties Malcolm Jenkins or Walter Thurmond at the position.

Watkins, a fourth-round pick in 2014, shuffled between cornerback and safety last season. He played in only four games as a rookie. But he has competed for a nickel spot this summer, taking first-team snaps on Sunday as part of the team's ongoing rotation.

Biggers made 31 career starts during the last five seasons in Washington and Tampa Bay. He also has experience in the slot. The Eagles signed him to a one-year deal this offseason. He's a serviceable veteran who offers experience at the position.

Evans and Rice are both rookies. Evans was a sixth-round pick who played slot cornerback at Kansas State. Rice is an undrafted free agent from Coastal Carolina who caught Kelly's eye this summer.

None of those options is likely to make observers forget Boykin, who was proven at the position.

Another scenario that could be appealing is playing second-round pick Eric Rowe as an outside cornerback when the Eagles go into the nickel formation, and moving either Carroll or Maxwell to the slot. Rowe is competing with Carroll to start. The Eagles are not training him in the slot. But Maxwell played the slot at times in Seattle, and Carroll was the Eagles' dime cornerback last season. Both would be able to play inside, which would allow the Eagles to get their second-round pick on the field.

The other option is remaining in the base defense even against three-receiver sets and using Jenkins or Thurmond to cover the slot receiver. Jenkins and Thurmond have experience in that role, and the Eagles have inside linebackers who can cover a tight end.

Shepherd will likely spend the season on injured reserve, but the Eagles must make a decision about whether to open a roster spot in the meantime. If they want to use Shepherd's spot on the 90-man roster for another player, they first must place Shepherd on waivers. If he goes unclaimed, Shepherd would revert to injured reserve. If the Eagles don't want to take that risk, they must wait until the roster is trimmed to 75 players on Sept. 1 to free his spot.

The Eagles put Travis Long on waivers last week to open his spot, and he went unclaimed. The Washington Redskins did the same with sixth-round pick Tevin Mitchel. The Indianapolis Colts claimed him, so the Redskins lost Mitchel before they could put him on injured reserve.

The Eagles were off on Monday. Kelly addresses reporters on Tuesday.

zberman@phillynews.com

@ZBerm