Iga Swiatek was bounced out of the U.S. Open’s round of 16 on Monday, collapsing after winning the first five games to suffer an upset loss to China’s Qinwen Zheng. Zheng, a 7-5, 6-3 victor, is on to the quarterfinals after needing to go through qualifiers to make the Open’s main draw while Swiatek — the 2022 champion here — was left talking of missed shots,