Before each day's play at the 2020 Australian Open, we'll preview three must-see matches.
 Serena Williams vs. Wang Qiang
Serena will face her first seeded opponent in No. 27 Qiang Wang. Whether that means she’ll face a tougher test than she did in her opening two rounds remains to be seen. These two women met in the quarterfinals at last year’s US Open, and…it didn’t end well for Wang. Despite having just knocked off world No. 1 Ash Barty, she managed to win just one game from Serena. Her clean, flat ground strokes fed right into Serena’s, and came back twice as hard. Still, we’ve seen players get destroyed by highly-ranked opponents before, and, their pride on the line, come back to surprise them later. Wang can’t do any worse this time around, right?
Winner: S. Williams
 Roger Federer vs. John Millman
We all remember what happened the last time these two met at a Grand Slam, at the 2018 US Open. Federer had trouble breathing in the newly enclosed Arthur Ashe Stadium, and Millman walked away with a four-set upset win. The Swiss and the Australian have played once since then, at Halle last year, and Federer got a measure of revenge with a 7-6 (1), 6-3 victory. Still, that’s not exactly a blowout. Millman can be a difficult opponent for Federer if he’s slightly off form; the Aussie grinder makes his opponents hit a lot of balls, and run a lot of yards, to beat him. And he knows he can do it to Federer, too.
Naomi Osaka vs. Coco Gauff
This completes our trilogy of US Open rematches. Osaka and Gauff played in New York last year, but the most memorable part of the evening came after the contest itself was over, when Osaka asked Gauff to share a post-match interview. What that heartwarming moment overshadowed, though, was the fact that Osaka completely dominated Gauff. After a few early jitters, Osaka began to make quick work of the rallies, and won it going away, 6-3, 6-0. Gauff, it seems safe to say, will do better this time. As we saw in her comeback win over Sorana Cirstea on Wednesday, she can go a long way on willpower alone. But I don’t think she can go this far.