The Denver Broncos continue to deal with serious injury issues at center. NFL.com's Ian Rapoport reported Sunday, per a source informed of the injury, that Dan Koppen is done for the season after suffering a torn anterior cruciate ligament in his left knee. Koppen was carted off the field after hearing a pop in the knee during practice. Koppen now heads toward surgery that will end his season -- and perhaps his career. Koppen, 33, signed with the Broncos last month after J.D. Walton was lost for the season after suffering a setback in his recovery from a dislocated ankle. Source: NFL.com
