Iga Swiatek admits the strict doping protocols can be stressful for players but feels like she has "been through the worst" after surviving her positive test over contaminated melatonin.
Swiatek said she made far too many mistakes against Keys on Rod Laver Arena and hoped to draw lessons from it.
The Polish second seed was phenomenal on a gusty day at Rod Laver Arena, powering past the eighth seeded-American 6-1, 6-2 in 1hrs 29mins.
Romania's Simona Halep on Friday rounded on the International Tennis Integrity Agency (ITIA) for discrepencies in the treatment of world number two Iga Swiatek after testing positive for a banned substance.
"The player was provisionally suspended from Sept. 22 until Oct. 4, missing three tournaments, which counts towards the sanction, leaving eight days remaining," the ITIA said in a statement.
The 26-year-old jumped above Poland's French Open champion Iga Swiatek thanks to year-end adjustments in the standings.
Top seed Swiatek, who won the title two years ago, showcased her all-court game in a straightforward 6-4, 6-1 win over Russian Liudmila Samsonova to open the evening session at Arthur Ashe Stadium and warned she was only going to improve.
Four-time French Open champion Swiatek was equally dominant as Sinner as the top-seeded Pole eased into the fourth round with a 6-4, 6-2 victory over Russia's Anastasia Pavlyuchenkova.
World number one Iga Swiatek of Poland withdrew from next week's WTA event in Toronto on Friday, citing fatigue from her run to a bronze medal at the Paris Olympics.
Ons Jabeur struggled to hold back the tears after losing a second consecutive Grand Slam final on Saturday, but while the Tunisian said her U.S. Open defeat to Iga Swiatek was tough to take she vowed to come back swinging.
Iga Swiatek surged to the third Grand Slam title of her career with a maiden victory at the US Open on Saturday, defeating Tunisia's Ons Jabeur in straight sets to extend her remarkable finals winning streak.
World number one Iga Swiatek rallied from a set down to beat Aryna Sabalenka 3-6 6-1 6-4 and reach her first U.S. Open final, where she will meet Ons Jabeur on Saturday for the trophy.
Rafael Nadal fell to his earliest US Open loss in six years on Monday when he was knocked out by Frances Tiafoe while Iga Swiatek became the first Polish woman to reach the quarter-finals.
Rafael Nadal defeated close friend Richard Gasquet for the 18th time to reach the US Open fourth round on Saturday as world number one Iga Swiatek made the last 16 for a second successive year.
French Open women's champion Iga Swiatek said she was "overwhelmed" after finding out Poland and Bayern Munich striker Robert Lewandowski was in attendance to witness her claim a second Grand Slam title on the Parisian clay.
Iga Swiatek cruised to her second French Open title by dominating teenager Coco Gauff in the final on Saturday, as the world number one claimed her 35th successive victory.
Iga Swiatek romped into her second French Open final on Thursday and will face Coco Gauff for the title after the teenager became the youngest Grand Slam finalist since 2004.
Unstoppable world number one Iga Swiatek racked up her 30th successive victory at the French Open on Thursday as 2021 runner-up Stefanos Tsitsipas survived another Roland Garros rollercoaster.
French Open favourite Iga Swiatek breezed into the second round at Roland Garros on Monday, beating Ukrainian qualifier Lesia Tsurenko 6-2, 6-0 to extend her winning run to 29 matches.
