The American world No. 1, under an injury cloud heading into the year’s first grand slam, was in control throughout a 6-4, 7-5 win at Rod Laver Arena.
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Williams, a 21-time grand slam champion, has had limited match practice because of knee inflammation during the Hopman Cup. But the defending champion was too good for the hard-hitting Italian Giorgi, the highest ranked unseeded player in the draw.
Williams showed plenty of emotion in the big moments despite rolling out to a 4-1 lead in the first set.
Giorgi managed to stay with Williams until the 11th game in the second set, but the latter broke thanks to a double fault before closing out her win.
STATISTICAL BREAKDOWN
Williams [1] def. Giorgi 6-4, 7-5
ACES
Williams - 9
Giorgi - 7
WINNERS/UNFORCED ERRORS
Williams - 19/22
Giorgi - 17/32
BREAK POINTS WON
Williams - 3/10
Giorgi - 1/1
FIRST SERVE PERCENTAGE
Williams - 53
Giorgi - 45
PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Williams - 86/65
Giorgi - 65/48
TOTAL POINTS
Williams - 79
Giorgi - 59