With the second 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.
Both sides of the draw are seeing strong play from past Grand Slam champions, including a surprising one on the women's side. Additionally, a clear favorite has emerged in the clash of the Williams sisters while one member of the men's Big 3 could face a stern third-round test from a player who raises his level against top opponents.
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Daniil Medvedev - After dispatching fellow Russian Evgeny Donskoy in the opening round, Medvedev knocked off 15th-seeded Stefanos Tsitsipas in four sets. Between his win at the Winston-Salem Open last week and his hot start in Flushing Meadows, Medvedev has won 18 of his last 19 sets heading into a third-round clash with 20th-seeded Borna Coric. Coric knocked off Medvedev in Cincinnati recently, but the 6-foot-6 Russian's tremendous results since then suggest he should fare better in this rematch.
Juan Martin del Potro - With an overwhelming mix of heat and humidity ravaging the field, getting off the court quickly has been essential. Del Potro has done just that, as neither of his first two matches even reached the two-hour mark. Fernando Verdasco turned some heads by eliminating an out-of-form Andy Murray in the second round, but del Potro has little to worry about against Verdasco in the Round of 32. The 2009 US Open champion is in excellent form while his 34-year-old opponent is in the third round at Flushing Meadows for the first time since 2012.
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Dominic Thiem - Few top guys had trouble in the second round, but Thiem got all he could handle from American Steve Johnson before ultimately escaping with a five-set win. The No. 9 seed came into the US Open on a three-match losing streak, which included defeats at the hands of unheralded opponents Nicolas Jarry and Martin Klizan. Given Thiem's underwhelming recent form, he's likely to struggle against 20-year-old American Taylor Fritz.
Sleeper
Nick Kyrgios - You never know what you're going to get from the enigmatic Aussie, but Kyrgios tends to play his best tennis against premier opponents. He's 1-2 against Roger Federer, 2-3 against Rafael Nadal and 2-0 against Novak Djokovic. Federer has uncharacteristically struggled with getting returns back in play during this hard-court season, and Kyrgios' massive serve will expose that weakness if the 30th seed brings his A-game for this third-round match.
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Serena Williams - Williams has looked very comfortable, dropping just four games apiece to each of her first two opponents. She's 10-5 against Venus in Grand Slams and has outplayed her older sister thus far at this tournament. Serena also has a major edge in freshness, having played two quick night matches while Venus has already spent almost five hours on court in the searing daytime heat. Whoever wins this family squabble will also be heavily favored against an unseeded opponent in the Round of 16.
Naomi Osaka - Osaka has always played well at the US Open. Two years ago at age 18, she upset Coco Vandeweghe in the first round before losing a third-round match to Madison Keys in a third-set tiebreak. In 2017, she again fell in the third round but took out Angelique Kerber along the way. The Osaka, Japan native looks primed to push into the second week this time around, as she's only lost seven games in her first two matches. In the 20th seed's way is world No. 33 Aliaksandra Sasnovich.
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Angelique Kerber - Speaking of Kerber, she looked ready to cruise through the second round with a 6-2, 5-2 lead over clay-courter Johanna Larsson, but then things got complicated. The Wimbledon champion's defensive style often allows opponents to dictate play, and a hot streak from Larsson helped the Swede come all the way back to take the second set, 7-5. While Kerber was able to triumph 6-4 in the third, she certainly looks vulnerable ahead of her third-round match against 29th-seeded Dominika Cibulkova. Cibulkova has reached at least the quarterfinals in a Grand Slam eight times, and Kerber's edge in their 12 head-to-head meetings is a narrow 7-5.
Sleeper
Victoria Azarenka - Azarenka's had a rough past few years, but the two-time Australian Open champion looks like she's starting to get her swagger back. She's yet to drop a set in this tournament and lost just three games to 25th-seeded Daria Gavrilova in the second round. Sloane Stephens came two games from getting knocked out by 124th-ranked Anhelina Kalinina on Wednesday, so the defending champ will have to raise her level if she wants to survive this clash with Azarenka.