“I don’t follow the rankings anymore, been there, done that,” Williams said.
Safina, eight times a finalist this season including last week in Cincinnati, could not find her feet on the Canadian hard court and contributed to her own demise by serving up 17 double faults.
The victory was the first win in three visits to Canada for Rezai and earned her a small measure of revenge for the 6-1, 6-0 hammering she suffered at the hands of the Russian in the French Open fourth round earlier this year.
With third seed Venus Williams already out, the top half of the draw has opened up for two former No. 1s on the comeback trail, Maria Sharapova and Kim Clijsters.
Sharapova, working her way back to top form after nine months recovering from shoulder surgery, also served up 17 double faults, but survived to book her place in the last 16 with a 6-3, 7-6 (7/5) win over Austria’s Sybille Bammer.
Clijsters, playing just her second event since coming out of a two-year retirement, battled to a 7-5, 4-6, 6-1 win over ninth-seeded Victoria Azarenka of Belarus.
Fifth seed Jelena Jankovic also advanced with a 7-5, 6-4 win over Swiss Patty Schnyder, while 11th-seeded Ana Ivanovic fell to Czech qualifier Lucie Safarova 3-6, 7-5, 6-3.
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