China could be in line for a late addition to its Tokyo 2020 medal haul after the Athletics Integrity Unit announced a provisional ban on British sprinter Chijindu Ujah over suspected doping.The body announced that there were adverse findings in the tests of 27-year-old Ujah, who ran the opening leg for Team GBs 4x100-metre sprint quartet as it was narrowly beaten by Italy and claimed Olympic silver ahead of Canada last w
