With the third round of the US Open in the books, it's time to highlight which players are on the rise and which ones look most vulnerable heading into the next round. Players who have been eliminated are of little interest to fantasy owners as the tournament unfolds, so this column is meant to take a look ahead based on what's happened so far rather than reflect on the past.
On the men's side, a pair of top-five seeds are on the rise heading into the fourth round. Things are looking up for a pair of American women, while a Czech teenager is making a name for herself in Flushing Meadows.
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Kevin Anderson - Anderson continues to display tremendous mental fortitude, having won a pair of five-set battles in this tournament to stretch his winning streak in such matches to four. The 2017 US Open runner-up likely won't need five sets to take care of Dominic Thiem in the Round of 16 despite the small difference in their rankings, as Thiem does most of his damage on clay while Anderson prefers faster surfaces like hard courts. Thiem has never been past the fourth round at the US Open and Anderson has won all six of their previous hard-court meetings.
Roger Federer - Federer is yet to drop a set in this tournament, and he easily got through what seemed like a tricky matchup with Nick Kyrgios, 6-4, 6-1, 7-5. Next up for the 20-time Grand Slam champion is 55th-ranked Australian John Millman, so expect Federer to cruise into the quarterfinals.
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David Goffin - Goffin didn't have to face a single seeded opponent on his way to the fourth round, but things are about to get significantly more challenging for the 10th-seeded Belgian. Hard courts are far from Goffin's favorite surface, as he came into this tournament with just a 7-6 career record at the US Open. His fourth-round opponent, Marin Cilic, won this tournament in 2014 and entered with a much more impressive 29-8 record in Flushing Meadows.
Sleeper
Milos Raonic - All four unseeded men left in the draw are heavy underdogs in the fourth round, leaving Raonic as the lowest-ranked player with a real chance of advancing to the quarterfinals. The big-serving Canadian finally looks healthy and has dropped just one set thus far while fourth-round opponent John Isner has already lost three. Isner is still the favorite in this match, but the outcome is likely to come down to a few key points since breaks of serve figure to be extremely rare.
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Serena Williams - Serena made this section after the second round, and her stock soared even higher with a 6-1, 6-2 demolition of sister Venus in a highly-anticipated third-round match. Up next for Williams is unseeded Kaia Kanepi. Kanepi upset top-seeded Simona Halep in the first round, but she's never won a set against Serena in four previous meetings.
Madison Keys - Keys has battled some injuries this season, but last year's US Open finalist appears to be peaking once again in New York. The No. 14 seed recovered beautifully after dropping the opening set to Aleksandra Krunic in the third round, coming away with a convincing 4-6, 6-1, 6-2 victory. In the Round of 16, she'll face 29th-seeded Dominika Cibulkova, who has never taken a set off Keys in four previous meetings.
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Elise Mertens - Mertens has lived up to her No. 15 seeding by reaching the fourth round of the US Open, but she'll be hard-pressed to go much further. Up next for her is the lone top-six seed left in the tournament, No. 3 Sloane Stephens. The defending champion looked vulnerable in a 4-6, 7-5, 6-2 second-round win over Anhelina Kalinina, but she took her game to a different level in the third round with a 6-3, 6-4 win over a very formidable opponent in Victoria Azarenka. Mertens had never won a US Open match prior to this tournament, and she'll be a considered an underdog against Stephens.
Sleeper
Marketa Vondrousova - Vondrousova is ranked 103rd, but the 19-year-old lefty is playing at a much higher level than that ranking suggests. In the third round, she came back from a break down in the final set to end 13th-seeded Kiki Bertens' eight-match winning streak, 7-6 (4), 2-6, 7-6 (1). Up next for Vondrousova is 36th-ranked Lesia Tsurenko, who entered this tournament with a 4-6 US Open record and a 20-28 mark in Grand Slams.