Serena Williams‘ road to a potential 24th Grand Slam singles title could be her toughest of them all — her last three matches at the Australian Open, if she advances, could be against the top three seeds.
Williams plays No. 2 Simona Halep in the quarterfinals on Tuesday (3 a.m. ET).
The winner gets either No. 3 Naomi Osaka or 71st-ranked Hsieh Su-wei, who at 35 is the oldest first-time women’s Grand Slam quarterfinalist in the Open Era (since 1968).
On the other half of the draw, just one of the four remaining players has Grand Slam final experience or is ranked in the top 20.