By Simon Evans MANHATTAN BEACH, California (Reuters) - Two of the leading players for the United States and Mexico national teams have given their backing to the idea of a regular Pan-American soccer tournament. The Copa America Centenario, bringing together the top teams from North and South America, was held in the United States last summer and there are reports of officials being interested in creating a similar tournament in the future. The centenary event was billed as a one-off but its commercial success has led to speculation that officials from South American confederation CONMEBOL and North and Central American body CONCACAF being interested in making it a regular event. More...