Source: Xinhua| Editor: huaxia Xinhua Sportswriters Xiao Shiyao, Gong Bing, Wu Xia SHANGHAI, Dec. 14 (Xinhua) -- The strictest ever expenditure and salary cap will be implemented in all levels of professional leagues next season, the Chinese Football Association (CFA) revealed here on Monday. In China's top flight, the Chinese Super League (CSL), the pre-tax annual income of an overseas player should be no more than three million euros (about 3.63 million US dollars), while the maximum salary for a domestic player is five million yuan (about 765,000 US dollars) per year before tax. "The policy aims to curb the investment bubbles in our leagues and promote the healthy and sustainable development of professional football," the CFA document read.