Complex sentence: The suburb of Mason hosts the Western & Southern Financial Group Masters & Women's Open, one of the nine (men's) tennis events in the ATP Tennis Masters Series and the only WTA Tour event in the Midwest.
Split into simpler sentences: The suburb of Mason hosts the Western & Southern Financial Group Masters & Women's Open. The men's Masters is one of the nine (men's) tennis events in the ATP Masters Series and the Women's Open is the only WTA Tour event in the Midwest.