England twice beat hosts United States to top pool B on day one of the UL International Crown in Chicago.
Holly Clyburn and Jodi Ewart Shadoff defeated Cristie Kerr and Lexi Thompson - the world number four - 2&1.
Then Charley Hull and Melissa Reid beat Gerina Piller and world number eight Stacy Lewis by the same score in the eight-team tournament.
"I just love playing in this kind of environment, especially when you are a bit of an underdog," Hull said.
Thailand and Japan make up the other teams in pool B while Chinese Taipei, Australia, South Korea and China are in pool A.
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