With the third round of the 2021 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 players 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.
The top contenders continued to roll on the top half of the men's draw, but the bottom half saw a pair of major shakeups in the third round, with No. 3 seed Stefanos Tsitsipas and No. 5 seed Andrey Rublev both crashing out in five-set thrillers. Meanwhile, the customary unpredictability in the women's draw reared its head in the third round after laying in wait. Arguably the top two contenders for the title both fell, with No. 1 seed Ashleigh Barty and No. 3 seed Naomi Osaka both failing to close out North American crowd favorites and ultimately succumbing in three sets. A number of players on both sides are poised to take advantage of the draws opening up, some due to pulling major upsets themselves and others because their paths forward have been cleared up for them.
Men
Stock Up
Carlos Alcaraz - It was only a matter of time until Alcaraz announced his presence as a player to reckon with on tour, and the 2021 US Open is officially the breakout tournament for the 18-year-old future star. The Spaniard overpowered No. 3 seed Stefanos Tsitsipas in a 6-3, 4-6, 7-6 (2), 0-6, 7-6 (5) third-round thriller, setting up a fourth-round clash with 141st-ranked Peter Gojowczyk. As long as the leg injury that Alcaraz got treatment for prior to the fifth set doesn't hinder him moving forward, he's in position to reach his first career Grand Slam quarterfinal and has a realistic shot at a semifinal berth with Frances Tiafoe -- who knocked off Rublev -- and No. 12 seed Felix Auger-Aliassime set to square off in the adjacent bracket of the draw from Gojowczyk and Alcaraz.
Daniil Medvedev - Medvedev has breezed through his first three rounds, dropping no more than eight games to Richard Gasquet, Dominik Koepfer or Pablo Andujar. While Djokovic and Zverev are rightfully earning headlines in the top half of the draw, the second-seeded Russian was the man to beat in the bottom half, even before the upsets poured in around him Friday. His draw remains relatively comfortable moving forward, as Medvedev will face 24th-seeded Daniel Evans in the fourth round and has no top-10 seeds left in his path to the final.
Reilly Opelka - Not only is Opelka in the Round of 16 of a major for the first time, but the highest-ranked of the three remaining American men (Jenson Brooksby and Frances Tiafoe are the others) has a golden opportunity to extend this career-best run further. Opelka's fourth-round opponent will be unseeded Lloyd Harris. Harris is enjoying a tremendous run, having upset both Karen Khachanov and Denis Shapovalov, but Opelka's overpowering serve gives him a weapon unlike anything Khachanov nor Shapovalov were able to throw at Harris.
Stock Down
Jannik Sinner - Sinner's in the Round of 16 as expected, but while the 13th-seeded Italian previously would have been a trendy upset pick, it's hard to see him troubling No. 4 seed Alexander Zverev, who has arguably played better than anyone else in the draw thus far. The 20-year-old Italian has dropped at least one set in every match at this tournament and just went 6-4 in the fifth against 17th-seeded Gael Monfils.
Sleeper
Oscar Otte - Otte's an amazing story who's playing with house money here. He needed third-set tiebreaks to get through each of the first two rounds of qualifying, but the 144th-ranked German now finds himself in the Round of 16. All the pressure will be on fellow big-server Matteo Berrettini when they face off in the first round, and while the sixth-seeded Berrettini will be the clear favorite, he hasn't played his best tennis thus far in this tournament. He went from a straight sets win in the opening round to four sets in the second and went to 6-3 in the fifth against Ilya Ivashka in the third round, so things have been far from comfortable for Berrettini despite him not having faced a seeded opponent.
Women
Stock Up
Angelique Kerber - The bottom half of the draw is wide open, and the resurgent Kerber is as ready as anybody to capitalize after recently reaching the semifinals at Wimbledon. Coming off a 5-7, 6-2, 6-3 win over Sloane Stephens in a third-round battle of former US Open, Kerber will now be favored in the fourth round against unseeded Canadian Leylah Fernandez in a matchup of crafty lefties. Fernandez just upset four-time Grand Slam champion and No. 3 seed Naomi Osaka, moving Kerber from a significant underdog to a favorite in the Round of 16.
Elina Svitolina - Svitolina has flown under the radar thus far, but the No. 5 seed is in fine form, having dropped only 18 games through three rounds. Fourth-round opponent Simona Halep has had a more successful career but she's still working her way back from recent injuries and narrowly escaped with a three-set win over Elena Rybakina in her third-round match. Svitolina and Halep have split 10 previous meetings, with Svitolina winning five of the last eight, so she has to fancy her chances here given each players' form coming in. The winner of their match will be favored to reach the semis in the wake of Osaka's loss.
Aryna Sabalenka - Osaka's defeat is reverberating all through the bottom half of the draw, where Sabalenka now has a clear path to her first major final. Since a shaky performance through the first two sets of her three-set first-round win, Sabalenka has been nearly flawless. The No. 2 seed has dropped only 10 games over her last five sets, overpowering opponents with blistering serves and groundstrokes. If Sabalenka's on her game, 15th-seeded Elise Mertens will struggle to keep up with her power in the Round of 16. Sabalenka leads their career head-to-head 4-2.
Stock Down
Iga Swiatek - Swiatek has needed three sets to get through each of her last two matchups, and she's about to face significantly stiffer competition. The No. 7 seed's fourth-round opponent will be 11th-seeded Belinda Bencic, who's playing arguably the best tennis of her career. Bencic won the gold medal at the Tokyo Olympics on hard court and hasn't dropped a set through three rounds.
Sleeper
Emma Raducanu - Raducanu just steamrolled Sara Sorribes Tormo 6-0, 6-1 in the third round, and the 18-year-old British qualifier has advanced to the Round of 16 without dropping a set in any of her three main draw matches, nor in any of her three matches in qualifying. The crowd will be against the 150th-ranked Raducanu against the last remaining American woman, and 43rd-ranked opponent Shelby Rogers just pulled off an epic comeback to upset world No. 1 Ashleigh Barty in a third-set tiebreak, but Raducanu's primed to keep her Cinderella run going if she's able to maintain her recent form.