Aryna Sabalenka continued her fine run of form by moving into the <a href="https://www.thenationalnews.com/tags/australian-open/" target="_blank">Australian Open</a> fourth round on Saturday, with the Belarusian yet to drop a set in 2023. Runner-up at the WTA Finals last year, Sabalenka has apologised for unsportsmanlike behaviour in the past, be it for throwing away her racquet or refusing to shake hands with opponents. Now the 24-year-old seems to be in a much better space. She won a warm-up event in Adelaide before extending her win streak in Melbourne with a straight sets victory over former doubles partner Elise Mertens 6-2, 6-3 on Margaret Court Arena emerge as a favourite for the first Grand Slam of the year.. "I need to be a little bit boring on court," Sabalenka told reporters. "It's still about a lot of positive emotions for me, but I'm trying to stay away from negative [emotions] and just fight for every point." Sabalenka said she would have to "stay low like a tiger" to beat in-form Belinda Bencic. Swiss Bencic was just as dominant in her 6-2, 7-5 victory over Italy's Camila Giorgi at the Rod Laver Arena. Sabalenka described how she would try to cope with Bencic and her big serve. "I feel like I have to stay really aggressive in the first few shots and then the slower ball or shorter ball will come," Sabalenka said at Melbourne Park. "It's all about fast feet on the first few shots. I have to be like a tiger, ready, stay low and be ready for that." Sabalenka needed just 74 minutes to beat Mertens - the pair won five titles together including the Australian Open in 2021 - but said it wasn't as easy as it looked. "It's really tough to play against her, especially. She's a great player, unbelievable fighter," said Sabalenka, who is yet to win a major. "I knew it's going to be tough. I'm super happy that I was able to stay focused from beginning to the end to win this match because she's an amazing player." Meanwhile, Holger Rune suffered a nasty-looking fall midway through his Australian Open third-round match against Ugo Humbert on Saturday but the ninth seed showed great fighting spirit to come out on top. A dark horse in Melbourne after his Paris Masters final victory over Novak Djokovic in November, the 19-year-old moved into the last 16 with a 6-4, 6-2, 7-6(5) win to book a fourth-round spot against Andrey Rublev. Seemingly struggling after turning his ankle and landing awkwardly, Rune needed lengthy treatment on court but it seemed to work. "It wasn't too bad," he told reporters. "I was able to play full. The third set, of course, I was a bit worried by what happened, but I saw the slow-motion after the match. Nothing dangerous. "I relaxed a lot more because I was a bit afraid, but honestly, I played very good after it happened. So I'm feeling hopeful." Also, home favourite Alex De Minaur stepped out of Nick Kyrgios's shadow and stormed into the last 16. Australian number two De Minaur ensured home fans will have someone to cheer in the second week as he steamrolled Frenchman Benjamin Bonzi 7-6(0), 6-2, 6-1.