Melbourne - World number one Angelique Kerber battled past Lesia Tsurenko in a stuttering start to her first Grand Slam title defence at the Australian Open on Monday.
The top seed ultimately proved too much for the Ukrainian, winning 6-2, 5-7, 6-2 on Rod Laver Arena and but the German's laboured victory was far from impressive.
Kerber, 28, stunned Serena Williams in the final last year and went on to win the US Open, dethroning the American powerhouse as the world's top ranked player.
She is not only defending a major title for the first time but also playing her maiden Grand Slam as top seed, admitting ahead of the tournament that she was carrying the burden of expectation.
She seemed to be struggling under that pressure early in the game, taking time to get into her groove. Once she did, there was no stopping her until Tsurenko came back to life late in the second set.
"The first round is always tough. I'm just trying to enjoy it and I'm so so happy to be in the second round," Kerber said.
"I'm really happy to be back in Melbourne because everything started for me here in 2016."
Bidding to be the first woman to defend her Australian title since Victoria Azarenka in 2013, the left-hander initially struggled to read the Ukrainian's serve.
Tsurenko, ranked 51 and in her seventh Australian Open, raced through her opening service game to love and Kerber had to save a break point in the next game to stay level.
Tsurenko kept the pressure on, firing down another love service game with the German seemingly at a loss.
But she finally got her eye in to break in the fifth game for a 3-2 lead and there was no looking back as she unleashed some powerful groundstrokes to take the first set in 27 minutes.
Tsurenko's confidence had taken a hit after losing six games in a row, including being broken in the first game of the second set, but she dug deep to rally and hold serve.
It looked like it was only delaying the inevitable but Kerber lost focus and failed to convert a match point in the 10th game, with the determined Tsurenko pouncing to break back and level the set at 5-5.
On a roll as Kerber flagged, she took the match to three sets when she converted a fourth set point while leading 6-5.
Kerber, who had an indifferent lead-up with early exits in Brisbane and Sydney this month, was rattled but regrouped for the deciding set, claiming the edge when the Ukrainian whipped a backhand wide in the fifth game to be broken.
The German kept her nerve and served out for the match to set up a second-round clash with fellow German Carina Witthoeft, who beat Japanese qualifier Eri Hozumi 7-5, 7-6 (8/6).
Collated results from the Australian Open on Monday:
Jeremy Chardy (FRA) bt Nicolas Almagro (ESP) 4-0 ret
Ryan Harrison (USA) bt Nicolas Mahut (FRA) 6-3, 6-4, 6-2
Tomas Berdych (CZE x10) bt Luca Vanni (ITA) 6-1 ret
Viktor Troicki (SRB x29) bt Damir Dzumhur (BIH) 6-4, 6-4, 2-6, 2-6, 6-3
Alex De Minaur (AUS) bt Gerald Melzer (AUT) 5-7, 6-3, 2-6, 7-6 (7/2), 6-1
Sam Querrey (USA x31) bt Quentin Halys (FRA) 6-7 (10/12), 7-6 (7/4), 6-3, 6-4
Mischa Zverev (GER) bt Guillermo Garcia-Lopez (ESP) 6-3, 7-6 (7/5), 6-4
Kei Nishikori (JPN x5) bt Andrey Kuznetsov (RUS) 5-7, 6-1, 6-4, 6-7 (6/8), 6-2
Bernard Tomic (AUS x27) bt Thomaz Bellucci (BRA) 6-2, 6-1, 6-4
Victor Estrella (DOM) bt Aljaz Bedene (GBR) 7-6 (9/7), 7-5, 0-6, 6-3
Andy Murray (GBR x1) bt Illya Marchenko (UKR) 7-5, 7-6 (7/5), 6-2
Andrey Rublev (RUS) bt Lu Yen-Hsun (TPE) 4-6, 6-3, 7-6 (7/0), 6-3
John Isner (USA x19) bt Konstantin Kravchuk (RUS) 6-3, 6-4, 6-7 (5/7), 6-1
Malek Jaziri (TUN) bt Go Soeda (JPN) 6-3, 6-4, 6-3
Diego Schwartzman (ARG) bt Pablo Cuevas (URU x22) 6-3, 6-3, 6-0
Dusan Lajovic (SRB) bt Stephane Robert (FRA) 6-3, 6-3, 6-3
Marin Cilic (CRO x7) bt Jerzy Janowicz (POL) 4-6, 4-6, 6-2, 6-2, 6-3
Alexander Bublik (KAZ) bt Lucas Pouille (FRA x16) 6-0, 3-6, 6-3, 6-4
Noah Rubin (USA) bt Bjorn Fratangelo (USA) 6-7 (4/7), 7-5, 3-6, 6-2, 6-2
Lukas Lacko (SVK) bt Albert Ramos (ESP x26) 4-6, 7-5, 1-6, 6-4, 6-3
Dudi Sela (ISR) bt Marcel Granollers (ESP) 5-7, 6-3, 6-2, 6-0
Steve Johnson (USA) bt Federico Del Bonis (ARG) 6-3, 6-4, 6-4
Paolo Lorenzi (ITA) bt James Duckworth (AUS) 6-4, 7-6 (7/4), 6-7 (4/7), 6-4
Andreas Seppi (ITA) bt Paul-Henri Mathieu (FRA) 6-4, 7-6 (7/4), 6-7 (3/7), 7-5
Nick Kyrgios (AUS x14) bt Gastão Elias (POR) 6-1, 6-2, 6-2
Jo-Wilfried Tsonga (FRA x12) bt Thiago Monteiro (BRA) 6-1, 6-3, 6-7 (5/7), 6-2
Karen Khachanov (RUS) bt Adrian Mannarino (FRA) 6-4, 3-6, 7-6 (11/9), 6-3
Jack Sock (USA x23) bt Pierre-Hugues Herbert (FRA) 6-4, 7-6 (7/4), 6-3
Dan Evans (GBR) bt Facundo Bagnis (ARG) 7-6 (10/8), 6-3, 6-1
Roger Federer (SUI x17) bt Jurgen Melzer (AUT) 7-5, 3-6, 6-2, 6-2
Stan Wawrinka (SUI x4) bt Martin Kližan (SVK) 4-6, 6-4, 7-5, 4-6, 6-4
Steve Darcis (BEL) bt Samuel Groth (AUS) 3-6, 6-3, 6-2, 6-2
Irina Begu (ROM x27) bt Yaroslava Shvedova (KAZ) 5-7, 6-3, 6-4
Samantha Crawford (USA) bt Lauren Davis (USA) 4-6, 6-3, 6-0
Garbine Muguruza (ESP x7) bt Marina Erakovic (NZL) 7-5, 6-4
Shelby Rogers (USA) bt Simona Halep (ROM x4) 6-3, 6-1
Mona Barthel (GER) bt Destanee Aiava (AUS) 6-3, 7-6 (7/4)
Monica Puig (PUR x29) bt Patricia Tig (ROM) 6-0, 6-1
Varvara Lepchenko (USA) bt Kiki Bertens (NED x19) 7-5, 7-6 (7/5)
Duan Yingying (CHN) bt Rebecca Sramkova (SVK) 6-3, 6-4
Julia Goerges (GER) bt Katerina Siniakova (CZE) 3-6, 6-3, 6-4
Jelena Jankovic (SRB) bt Laura Siegemund (GER x26) 6-1, 1-6, 6-4
Alison Riske (USA) bt Madison Brengle (USA) 7-5, 6-3
Kristyna Pliskova (CZE) bt Viktorija Golubic (SUI) 6-3, 2-6, 6-4
Sorana Cirstea (ROM) bt Irina Khromacheva (RUS) 6-2, 6-1
Anastasija Sevastova (LAT x32) bt Nao Hibino (JPN) 6-4 ret
Kristina Kucova (SVK) bt Christina McHale (USA) 6-4, 6-0
Venus Williams (USA x13) bt Kateryna Kozlova (UKR) 7-6 (7/5), 7-5
Natalia Vikhlyantseva (RUS) bt Vania King (USA) 6-3, 6-2
Jaimee Fourlis (AUS) bt Anna Tatishvili (USA) 6-4, 6-3
Zhang Shuai (CHN x20) bt Aliaksandra Sasnovich (BLR) 6-0, 6-3
Pauline Parmentier (FRA) bt Misaki Doi (JPN) 7-5, 7-5
Coco Vandeweghe (USA) bt Roberta Vinci (ITA x15) 6-1, 7-6 (7/3)
Ashleigh Barty (AUS) bt Annika Beck (GER) 6-4, 7-5
Stefanie Voegele (SUI) bt Kurumi Nara (JPN) 2-6, 6-2, 6-3
Elina Svitolina (UKR x11) bt Galina Voskoboeva (KAZ) 6-0, 6-2
Julia Boserup (USA) bt Francesca Schiavone (ITA) 6-2, 6-4
Anastasia Pavlyuchenkova (RUS x24) bt Evgeniya Rodina (RUS) 6-1, 7-6 (7/2)
Svetlana Kuznetsova (RUS x8) bt Mariana Duque (COL) 6-0, 6-1
Angelique Kerber (GER x1) bt Lesya Tsurenko (UKR) 6-2, 5-7, 6-2
Carina Witthoeft (GER) bt Eri Hozumi (JPN) 7-5, 7-6 (8/6)
Peng Shuai (CHN) bt Darya Kasatkina (RUS x23) 6-0, 7-6 (7/5)
Carla Suarez (ESP x10) bt Jana Cepelova (SVK) 6-2, 6-2
Eugenie Bouchard (CAN) bt Louisa Chirico (USA) 6-0, 6-4