Melbourne - Russian star Maria Sharapova survived a major scare before dousing the challenge of Italy's Karin Knapp in intense heat to reach the Australian Open third round on Thursday.
The third seed battled through temperatures of up to 42 Celsius and a third set lasting nearly two hours to overcome the 44th-ranked Knapp 6-3, 4-6, 10-8.
The four-time Grand Slam champion was forced to stay on court for three hours 28 minutes as she seeks her first major title since the French Open in 2012.
The conditions were so tough that organisers suspended play at the tournament midway through the third set. However, under tournament rules, Sharapova and Knapp had to finish the set before coming off.
"It was tough for both of us and we both fought as hard as we could," said Sharapova.
"The recovery for me will be really important but these are the matches you train for and I'm really happy to be through."
Now under coach Sven Groeneveld after a failed, one-tournament partnership with Jimmy Connors, the 26-year-old is coming back from shoulder surgery, and she struggled against Knapp.
Her serve let her down and she only converted seven of 20 break points.
Sharapova got the match at Rod Laver Arena underway by holding serve and Knapp did the same as the two players got the measure of their games.
Sharapova had struggled with her serve in the first round and it again posed a problem, with three double faults in the third game allowing Knapp to get an unexpected break.
But the Italian failed to make the most if it, losing her next service game to love as Sharapova's probing baseline shots started finding their mark.
The Russian, at her 11th Australian Open, which she won in 2008, held serve to go 3-2 in front and began applying the pressure, finally getting another break but not before throwing away three break points.
Sharapova held as Knapp started wilting in the oven-like conditions and she served out the set before donning an ice vest and gulping water at the changeover as she desperately tried to cool down.
They both held their opening serve in the second set before a feeble Knapp double-fault put Sharapova 2-1 in front, only for the Italian to level at 2-2 when her opponent sent a forehand long.
It went with serve in close-fought games until backhand into the net gave Knapp three set points and a backhand long made it one set apeice.
The heat rule was in effect, giving them a 10-minute break between the second and third sets, and Sharapova returned refreshed, firing cross-court winners to break for 1-0.
But she then failed to hold serve, as did Knapp with the Russian again gaining the edge. Once again, Sharapova was broken to leave the match finely poised at 3-3.
She got another break and had three match points in the 10th but threw them away and with Knapp then holding, Sharapova had to serve twice to stay in the match before breaking in the 17th and serving out for victory.
Sharapova, who returned from injury at the Brisbane International this month, next plays French 25th seed Alize Cornet.
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