Dayana Yastremska was the first qualifier to reach the Australian Open semifinals since Christine Matison in 1978,[6] and the third Ukrainian (male or female) to reach a major semifinal, after Elina Svitolina and Andrei Medvedev.[7] Zheng became the second Chinese to reach a major singles final, after Li Na,[8] and the second player in the Open Era to beat six unseeded players en route to the final after Arantxa Sánchez Vicario in 1995,[9] and the third player to do so at any major (after Sánchez Vicario and Martina Hingis at 1996 and 1997 Wimbledon, respectively, with the 16-seeds draw still in place). By reaching the final, Zheng made her debut in the top ten of the WTA rankings.[10]
For the first time in the tournament's history, there were six former champions in the main draw: Sabalenka, Naomi Osaka, Sofia Kenin, Caroline Wozniacki, Angelique Kerber, and Victoria Azarenka.[11] This was the final Australian Open appearance for 2016 champion Kerber, who lost to Danielle Collins in the first round.
The defeat of world No. 1 Iga Świątek by Linda Nosková in the third round marked the earliest loss by a top seed at the Australian Open since 1979,[12] and the first time that the top seed failed to make the round of 16 since the tournament became a 128-player draw in 1988. Nosková was the first teenager to defeat a current world No. 1 at a major since Petra Kvitová defeated Dinara Safina at the 2009 US Open.[13] The five top-10 seeds to reach the third round were the fewest since 1988.[14] Only seven seeded players reached the fourth round; this was the worst performance by seeded players since the draw was expanded to 128 players in 1988, and the worst overall since 1985.[citation needed]
Elena Rybakina and Anna Blinkova played the longest tiebreak in a major singles match in the third set of their second-round match. Blinkova won the tiebreak 22–20.[14]