Melbourne - In-form fourth seed Agnieszka Radwanska overcame tough first set resistance from local qualifier Bojana Bobusic to book her place in the second round of the Australian Open Monday.
The Pole, who won lead-up events in Auckland and Sydney, was pushed hard in the first set before winning 7-5, 6-0 in 79 minutes and will next face either Arantxa Rus of the Netherlands or Romania's Irina-Camelia Begu.
Radwanska came into the tournament as the hottest women's player on tour but her nine straight match wins ahead of the clash with little-known Bobusic seemed to have taken their toll, with a see-sawing first set.
The world number four, who has made the quarter-finals at Melbourne three times but never gone further, was broken in her opening service game as she struggled to find her feet on the Margaret Court Arena.
She fought back to break the feisty Bobusic to make it 1-1 but the Pole was broken again in the fifth game to put the pressure on.
Radwanska rallied against a boisterous home crowd to break back again and eventually take the set 7-5 with a backhand winner off a weak Bobusic second serve.
The effort of the first set took its toll on the Australian who collapsed in the second set, failing to win another game as Radwanska, a Wimbledon finalist last year, stamped her class on the match.
Results from day one of the Australian Open on Monday:
Maria Sharapova (RUS x2) bt Olga Puchkova (RUS) 6-0, 6-0
Venus Williams (USA x25) bt Galina Voskoboeva (KAZ) 6-1, 6-0
Li Na (CHN x6) bt Sesil Karatantcheva (KAZ) 6-1, 6-3
Julia Goerges (GER x18) bt Vera Dushevina (RUS) 7-5, 2-6, 6-4
Sorana Cirstea (ROM x27) bt Coco Vandeweghe (USA) 6-4, 6-2
Kristyna Pliskova (CZE) bt Sacha Jones (AUS) 6-3, 6-2
Romina Oprandi (SUI) bt Tsvetana Pironkova (BUL) 4-6, 7-5, 6-2
Olga Govortsova (BLR) bt Pauline Parmentier (FRA) 2-6, 6-3, 6-2
Samantha Stosur (AUS x9) bt Chang Kai-chen (TPE) 7-6 (7/3), 6-3
Agnieszka Radwanska (POL x4) bt Bojana Bobusic (AUS) 7-5, 6-0
Misaki Doi (JPN) bt Petra Martic (CRO) 6-3, 6-4
Jelena Jankovic (SRB x22) bt Johanna Larsson (SWE) 6-2, 6-2
Klara Zakopalova (CZE x23) bt Chanelle Scheepers (RSA) 6-1, 6-2
Ekaterina Makarova (RUS x19) bt Michelle Larcher De Brito 6-2, 7-5
Kirsten Flipkens (BEL) bt Nina Bratchikova (RUS) 6-4, 6-3
Julien Benneteau (FRA x32) bt Grigor Dimitrov (BUL) 6-4, 6-2, 6-4
Xavier Malisse (BEL) bt Pablo Andujar (ESP) 6-3, 6-1, 6-2
Kei Nishikori (JPN x16) bt Victor Hanescu (ROM) 6-7 (5/7), 6-3, 6-1, 6-3
Nicolas Almagro (ESP x10) bt Steve Johnson (USA) 7-5, 6-7 (4/7), 6-2, 6-7 (6/8), 6-2
Stanislas Wawrinka (SUI x15) bt Cedrik-Marcel Stebe (GER) 6-2, 6-4, 6-3
Guillaume Rufin (FRA) bt Julian Reister (GER) 4-6, 7-6 (7/4), 6-1, 6-2
Tomas Berdych (CZE x5) bt Michael Russell (USA) 6-3, 7-5, 6-3
Edouard Roger-Vasselin (FRA) bt Ruben Bemelmans (BEL) 6-3, 6-7 (5/7), 6-3
Ryan Harrison (USA) bt Santiago Giraldo (COL) 2-6, 6-4, 7-5, 6-4
Evgeny Donskoy (RUS) bt Adrian Ungur (ROM) 6-4, 6-4, 6-2
Carlos Berlocq (ARG) bt Maxime Authom (BEL) 1-6, 7-6 (7/5), 7-6 (7/4), 6-2
Daniel Gimeno-Traver (ESP) bt Lukasz Kubot (POL) 6-7 (4/7), 6-4, 6-0, 4-6, 6-4
Fernando Verdasco (ESP x22) bt David Goffin (BEL) 6-3, 3-6, 4-6, 6-3, 6-4
Novak Djokovic (SRB x1) bt Paul-Henri Mathieu (FRA) 6-2, 6-4, 7-5
Jurgen Melzer (AUT x26) bt Mikhail Kukushkin (KAZ) 6-1, 6-1, 6-2