Open second round on Thursday.
Keys, runner-up in 2017 and a semi-finalist in 2018, won the first three games against her unseeded opponent, who broke her serve after a pair of unforced errors late in the first set but was unable to catch up.
Keys, who defeated Timea Babos in 55 minutes on Tuesday, committed more than a dozen unforced errors but more than made up for it with her trademark aggressive forehand and monster serve, launching six aces.
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Keys faces France's Alize Cornet in the third round. (Reporting by Amy Tennery, editing by Ed Osmond)
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