Aoyama and Shibahara prevail in opening round-robin match at WTA Finals
No.3 seeds Shuko Aoyama and Ena Shibahara beat No.5 seeds Desirae Krawczyk and Demi Schuurs 7-5, 6-2 and took an early lead in the Maya Ka'an Group at the GNP Seguros WTA Finals Cancun.