updated 12:55 p.m. ET July 24, 2008

ALLEN PARK, Mich. - Caleb Campbell said he was upset when the Army told him he wouldn’t be able to play for the Detroit Lions this season.

“Oh yeah, I cried, because I wanted a shot,” Campbell, a seventh-round draft pick of the Lions, told The Oakland Press of Pontiac for a story published Thursday.

The West Point graduate initially was told by the Army he could enter the NFL draft this year. If he made the team, he was told, he would be allowed to play in Detroit and carry out his service as a recruiter in the area.

“I had the best of both worlds,” Campbell told the newspaper.

But military policy was reinterpreted in recent weeks. The Army on Wednesday officially informed Campbell, a second lieutenant, and the Lions that he would be required to serve at least two years on active duty before he could apply to be released.

He already had agreed to terms with the Lions and was due to start training camp Thursday.

Campbell said he “didn’t ask for it, but you should never have gave it to me if it wasn’t going to happen.”

The Army wrote in its letter to Lions president Matt Millen that it acted in good faith.

Despite his disappointment, Campbell said he is “really excited” for his next assignment — a year as a graduate assistant football coach for the Army, either at the U.S. Military Academy or the service academy’s preparatory school.

After a year, he said, he will report to officer training.

“I was initially shocked, but you know when duty calls,” Campbell said. “I can’t do much about it. I’m being optimistic about everything, taking it with a smile, having a good attitude about it, disappointed that I didn’t get my one shot, but that’s OK because when I went to the academy I initially went to the academy to be an officer.”