Melbourne - Australian Open 10th seed Caroline Wozniacki is one those players that has been world number one yet never won a Grand Slam.
But the Dane, now happy her personal and professional life after getting engaged to golf star Rory McIlroy, believes she can go all the way at Melbourne Park this year.
Wozniacki on Thursday overcame a second set meltdown in intense heat to beat unseeded American Christina McHale 6-0, 1-6, 6-2 and make the third round, where she will play the dangerous Garbine Muguruza.
Despite the mid-match wobble, she is confident of a good run at Melbourne Park.
"I think you always believe you can win, but I still have quite a few matches to go. So I'm just thinking one match at a time," she said.
The Dane ended 2010 and 2011 as world number one but she has made just one Grand Slam final so far, at the 2009 US Open.
Her title credentials will be tested by Spain's Muguruza, who is on a hot run of form after winning her first WTA tournament at the Hobart International this month.
"She's definitely on a roll, she won Hobart," said Wozniacki. "She's playing well, she's playing aggressive. Not very typical Spanish, because she goes in and attacks the ball, plays very heavy.
"It's going to be a tough match but I'm excited about it. I'm excited to have won today and be through to the third round."
Results from the Australian Open on Thursday:
Kei Nishikori (JPN x16) bt Dusan Lajovic (SRB) 6-1, 6-1, 7-6 (7/3)
Jo-Wilfried Tsonga (FRA x10) bt Thomaz Belluci (BRA) 7-6 (8/6), 6-4, 6-4
Rafael Nadal (ESP x1) bt Thanasi Kokkinakis (AUS) 6-2, 6-4, 6-2
Donald Young (USA) bt Andreas Seppi (ITA x24) 6-4, 2-6, 6-3, 4-6, 7-5
Roger Federer (SUI x6) bt Blaz Kavcic (SLO) 6-2, 6-1, 7-6 (7/4)
Stephane Robert (FRA) bt Michal Przysiezny (POL) 7-6 (7/3), 6-1,
6-7 (3/7), 6-1
Gael Monfils (FRA x25) bt Jack Sock (USA) 7-6 (7/2), 7-5, 6-2
Grigor Dimitrov (BUL x22) bt Lu Yen-Hsun (TPE) 6-3, 6-3, 7-6 (11/9)
Milos Raonic (CAN x11) bt Victor Hanescu (ROM) 7-6 (11/9), 6-4, 6-4
Martin Klizan (SVK) bt Blaz Rola (SLO) 6-4, 6-3, 5-7, 7-6 (7/2)
Feliciano Lopez (ESP x26) bt Michael Berrer (GER) 6-4, 7-6 (8/6), 6-4
Andy Murray (GBR x4) bt Vincent Millot (FRA) 6-2, 6-2, 7-5
Roberto Bautista Agut (ESP) bt Juan Martin del Potro (ARG x5) 4-6, 6-3, 5-7, 6-4, 7-5
Teymuraz Gabashvili (RUS) bt Fernando Verdasco (ESP x31) 7-6 (7/1), 3-6, 2-6, 6-4, 6-4
Gilles Simon (FRA x18) bt Marin Cilic (CRO) 4-6, 7-6 (7/3), 6-7 (5/7), 6-1, 6-2
Benoit Paire (FRA x27) bt Nick Kyrgios (AUS) 6-7 (5/7), 6-7 (5/7), 6-4, 6-2, 6-2
Women's singles:Second round:
Zarina Diyas (KAZ) bt Marina Erakovic (NZL) 6-4, 6-0
Anastasia Pavlyuchenkova (RUS x29) bt Mandy Minella (LUX) 6-2, 6-2
Elina Svitolina (UKR) bt Olivia Rogowska (AUS) 6-4, 7-5
Simona Halep (ROU x11) bt Varvara Lepchenko (USA) 4-6, 6-0, 6-1
Carla Suarez Navarro (ESP x16) bt Galina Voskoboeva (KAZ) 7-6 (7/2), 3-6, 8-6
Dominika Cibulkova (SVK x20) bt Stefanie Voegele (SUI) 6-0, 6-1
Alize Cornet (FRA x25) bt Camila Giorgi (ITA) 6-3, 4-6, 6-4
Maria Sharapova (RUS x3) bt Karin Knapp (ITA) 6-3, 4-6, 10-8
Garbine Muguruza (ESP) bt Anna Schmiedlova (SVK) 6-3, 6-3
Agnieszka Radwanska (POL x5) bt Olga Govortsova (BLR) 6-0, 7-5
Caroline Wozniacki (DEN x10) bt Christina McHale (USA) 6-0, 1-6, 6-2
Sloane Stephens (USA x13) bt Ajla Tomljanovic (CRO) 3-6, 6-2, 7-5
Victoria Azarenka (BLR x2) bt Barbora Zahlavova Strycova (CZE)
Kurumi Nara (JPN) bt Magdalena Rybarikova (SVK x32) 6-4, 6-3
Jelena Jankovic (SRB x8) bt Ayumi Morita (JPN) 6-2, 6-0
Yvonne Meusburger (AUT) bt Bojana Jovanovski (SRB x33) 3-6, 6-3, 6-2
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