Track and field starts ; women begin quest for 100-meter title . U.S. , Saudi meet again in 100-meter butterfly final . Soccer quarters feature Phelps against Group E. . Saudi woman takes Maria Sharapova mat .
Track and field starts ; women begin quest for 100-meter title . Phelps , Cavic meet again in 100-meter butterfly final . Soccer quarters feature U.S. against the Football Ferns . Saudi woman takes judo mat .