Radio Works'acquisition of WRWC(FM) Rockford, Ill., is the latest radio deal to be criticized by FCC Commissioner Gloria Tristani. After the agency's March 31 approval, the purchase puts 95% of the market's advertising revenue in the hands of two companies, the other being Cumulus Media. "This increased concentration effectively eliminates the possibility that a third competitor could enter the Rockford market," she said in a written statement denouncing the agency's approval of the deal. The market power will enable the two powerful companies to engage in price discrimination and collusive behavior, she said. Rather than approving the deal with a cursory review, Tristani said the agency should have forced Radio Works to show that the Rockford market cannot support three competitors or that wrwc was losing money and no other buyers were available.