Dallas Cowboys star Dak Prescott sent out a classy message to former backup Cooper Rush after his departure from the team in NFL free agency.

Cooper Rush had a steady stint as Dak Prescott's backup, but not spectacular enough to be ranked among the Dallas Cowboys' Top 10 best No. 2s.

It had to be done. The idea of Cooper Rush was not always as good as advertised. The former Central Michigan star has spent the bulk of his NFL career serving a

The number behind the starter can quickly become just as important, a lesson the Dallas Cowboys learned during the Tony Romo years and, more recently, during the Dak Prescott era. MORE: Updated list of Cowboys NFL Draft picks after free agency's first week While Dallas is not overly concerned about the position with Prescott returning from a season-ending hamstring injury,

The Cowboys have $37.6 million in effective cap space, the 10th-most in the NFL, after an active free agency run