Jo Konta withdrew from the US Open as fellow Briton Emma Raducanu will now face Stefanie Voegele, who replaces the injured Jennifer Brady.
30-year-old Konta had been due to face France's Kristina Mladenovic on Monday evening in the first round.
It is believed that an on-going knee injury is the reason for her withdrawal.
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Raducanu's opponent Brady pulled out on Monday around midday as a result of a knee injury. She was replaced by Switzerland’s Voegele, who had lost in the final round of qualifying.
Brady had pedigree as the 13th seed and was also losing finalist in this season’s Australian Open, and also reached the semi-finals of 2020’s US open. 31-year-old Voegele has often struggled to crack the top hundred, and is yet to make a dent on the majors.
However Voegele still has experience on the professional tour to dwarf that of 18-year-old Raducanu, and it will throw out any preparation that the Briton has done on her expected opponent.
The teenager may still be considered the favourite after her fourth-round exit at this summer’s Wimbledon, regardless of breathing difficulties which forced her retirement against Alja Tomljanovic, given her assured performances in America so far over the last two months.
“I was feeling very confident out there after the amount of matches I had in the last few weeks,” earlier said to the press.
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