Cowboys owner Jerry Jones is ‘convinced’ QB Dak Prescott can get better

Dak Prescott has established himself as one of the better quarterbacks in the NFL, but Dallas Cowboys owner Jerry Jones feels that there’s still another gear for the 30-year-old to reach.

“We just have in mind the team that’s going on the field this year, and we all know that every team in this league has limitations as far as where they are on the cap and where they are in the draft and where they are with their free agents, who they can…