The salaries for the second-round draft picks range from $1,579,416 to $952,995. Third-round pick salaries range from $899,198 to $818,073. The day two selections in the second and third round will all receive four-year contracts.
Even a 3rd rounder gets nearly a mil for four years. Why pass that up to stay in college? Who might stay instead of going out?
In theory, a 3rd round QB might improve over his final year enough to be a first day pick. Now we're talking $13 million at the bottom end, up to over $40. So, I think IF you think another year will boost your draft status, it makes sense to stay.