The seeds came out to play on the women’s side on Thursday at the Sony Open in Miami, where six top players were promptly sent home.
The highest-profile exit was No. 10 Marion Bartoli, who retired down 6-3, 4-1 against back-from-injury Andrea Petkovic of Germany.
Also orchestrating upsets were Swiss Romina Oprandi edging No. 17 Lucie Safarova 7-6 in the third, Slovak Maggie Rybarikova defeating No. 27 Mona Barthel 6-3, 7-6(5), Spain’s Garbine Muguruza Blanco coming from a set down to defeat No. 23 Anastasia Pavlyuchenkova, Japan’s Ayumi Morita outlasting No. 31 Yanina Wickmayer in three, and Croat Ajla Tomljanovic ousting No. 24 Julia “Gorgeous” Goerges 7-6(4), 6-2.
In Top 10 play No. 1 Serena Williams rolled Flavia Pennetta 6-1, 6-1; No. 4 Aggie Radwanska eased past Taiwan’s Hsieh Su-Wei 6-3, 6-2; No. 5 Li Na strolled past Dutchwoman Kiki Bertens 6-3, 6-1; No. 7 Petra Kvitova came from a set down to defeat China’s Peng Shuai 5-7, 6-2, 6-2; and No. 9 Caroline Wozniacki likewise struggling to beat Czech Karolina Pliskova 5-7, 6-3, 6-3.
“My attitude is that it always feels better when you’re No.1,” Williams opined. “There’s nothing like when they announce you and they say, ‘The No. 1 player in the world.’ So for me it definitely gives me a little bit more confidence, I think a little bit more pep in your step. It’s just a great feeling. This keeps me going — I’m No. 1, I’m pretty good at it still. If I’m doing something well, I don’t want to stop, and I shouldn’t stop. I don’t have to play another match, but I’m having fun, I’m enjoying it. Normally the history books wouldn’t really matter to me but when you get closer to a goal, you can’t help but start thinking, ‘Okay, I want to do history.’ In retrospect I have made history already, so I just try to keep it going a little bit at a time. I don’t know if I could ever top Margaret Court’s record, but it would be exciting to try and reach some of my fellow countrywomen who are ahead of me.”
Radwanska had a determined start in defending her title from last year.
“It was a really special tournament for me because I was really playing a lot of good matches against top players and not even losing a set,” Radwanska said. “I definitely have great memories from here. And the final was a very good match. Hopefully I can play the same level of tennis this year.”
Other seeded winners were No. 13 Dominika Cibulkova, No. 16 Sloane Stephens after dropping the first set 6-0, No. 25 Varvara Lepchenko, and No. 30 Kirsten Flipkens.
“It’s not that I wasn’t playing great, I was just asleep out there — I definitely needed to wake up and start playing,” Stephens said after getting fed a bagel by Olga Govortsova. “I thought I played some good points even in the first set when I was not there. It was a lot of battling and just hanging in there, and I think after I won a game in the beginning of the second set I was much better and thought, ‘I’m just going to go ahead and play.’”
On the men’s side it was still all-unseeded scrub play, with Jarkko Nieminen coming from a set down to defeat David Nalbandian, and other notable winners Ivan Dodig, David Goffin, Viktor Troicki, and Bernard Tomic.
Tomic will next meet No. 2 seed Andy Murray.
Highlights of Friday matches are (2) Victoria Azarenka vs. (WC) Madison Keys, Canadian (WC) Eugenie Bouchard vs. (3) Maria Sharapova, (8) Sara Errani vs. Daniela Hantuchova, (18) Ekaterina Makarova vs. former No. 2 Svetlana Kuznetsova, (WC) James Blake vs. (24) Julien Benneteau, (19) Alexandr Dolgopolov vs. Nikolay Davydenko, (11) Gilles Simon vs. (WC) Lleyton Hewitt, (22) Jelena Jankovic vs. (WC) Victoria Duval, (6) Angelique Kerber vs. former Slam champ Francesca Schiavone, (14) Maria Kirilenko vs. (Q) Bethanie Mattek-Sands, and American comer Jamie Hampton vs. (20) Carla Suarez Navarro.
SCHEDULE – FRIDAY, 22 MARCH, 2013
STADIUM start 11:00 am
[WC] M Keys (USA) vs  V Azarenka (BLR) – WTA
 D Ferrer (ESP) vs [Q] D Tursunov (RUS) – ATP
Not Before 3:00 PM
T Kamke (GER) vs  J Del Potro (ARG) – ATP
Not Before 5:00 PM
[WC] E Bouchard (CAN) vs  M Sharapova (RUS) – WTA
Starting at 8:00 PM
 N Djokovic (SRB) vs L Rosol (CZE) – ATP
 S Errani (ITA) vs D Hantuchova (SVK) – WTA
GRANDSTAND start 11:00 am
 E Makarova (RUS) vs S Kuznetsova (RUS) – WTA
[WC] J Blake (USA) vs  J Benneteau (FRA) – ATP
 A Dolgopolov (UKR) vs N Davydenko (RUS) – ATP
 G Simon (FRA) vs [WC] L Hewitt (AUS) – ATP
Not Before 5:00 PM
 J Jankovic (SRB) vs [WC] V Duval (USA) – WTA
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