Greece starts title defence with loss to Olympic champion USA

In Group B action, World League champion China nearly kept South Africa scoreless with a handsome 17-2 victory and world No 3 Australia earlier dispensed with New Zealand 15-4.

In Group D, Hungary romped home 20-6 over Brazil and Italy came back from 3-0 down to Kazakhstan to rebound 8-3 and finally come home 9-7.

Women's points after day one:

Group A: RUS 2, ESP 2, NED 0, UZB 0.
Group B: CHN 2, AUS 2, NZL 0, RSA 0.
Group C: CAN 2, USA 2, GRE 0, GBR 0.
Group D: HUN 2, ITA 2, KAZ 0, BRA 0.