Cozumel|Esther Nuñez|FINA Open Water Swimming Grand Prix|Olga Kozydub|pilar geijo

A week after the 10K marathoners visit Cozumel on the Yucatan Peninsula in Mexico, the ultra-marathoners fly in and compete in the most beautiful and shortest leg on the FINA Open Water Swimming Grand Prix pro circuit. Young Olga Kozydub of Russia is just barely hanging on to a slim series lead over the two…