The World No. 1 was seen by the tournament doctor twice and appeared to be given a fruit bar -- her coach Patrick Mouratoglou told reporters she was dizzy -- but even an under-the-weather Williams can win grand slams.
Indeed, the way Williams dispatched a surely crestfallen Sharapova, all signs point to the American landing in Saturday's finale, and perhaps against the surging Victoria Azarenka.
Sharapova hadn't beaten Williams since 2004 but taking a 2-0 lead on a sunny day with temperatures around 30 degrees Celsius must have given fans of the world's richest female athlete hope.