Terms of the deal announced Monday night were not available.
Watkins, the 23rd pick in this year's draft, missed the first five days of training camp at Lehigh University.
Watkins, 26, did not play competitive football until he was a 22-year-old student of firefighting science at Butte Community College in Northern California in 2007. He played the last two years at Baylor.
The Eagles have been trying to solidify the right guard position since former first-round pick and two-time Pro Bowl pick Shawn Andrews began struggling with a serious back injury soon after the 2007 season.