The Dallas Cowboys have signed guard Jonathan Cooper, hoping the top 10 pick from 2013 can provide depth in the playoffs on the injury-plagued left side of the line Cowboys sign former top 10 pick Cooper for depth on line The Dallas Cowboys have signed guard Jonathan Cooper, hoping the top 10 pick from 2013 can provide depth in the playoffs on the injury-plagued left side of the line Check out this story on USATODAY.com: http://usat.ly/2j5ZMW8 FRISCO, Texas – The Dallas Cowboys have signed guard Jonathan Cooper, hoping the top 10 pick from 2013 can provide depth in the playoffs on the injury-plagued left side of the line.