Fifth seed Serena, the 2008 Charleston champion, hammered 11 aces in overpowering last year’s runner-up Elena Vesnina, 6-3, 6-4, in a second-round match at the $740,000 event.
World No 87 Venus, who returned to the tour last month in Miami after being out seven months due to illness, needed just 79 minutes to dispatch qualifier Iveta Benesova of the Czech Republic, 6-4, 6-3, in the first round.
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