The American quartet, anchored with a stunning final leg by Carmelita Jeter, timed 40.82sec to slice more than half a second off the 27-year-old record of 41.37sec set by the former East Germany in 1985.

“I knew we were running fast. I was already pointing at the clock, saying ‘there it is’,” said 32-year-old Jeter. I knew that if we got the stick around then all I had to do was to bring it home,” said Jeter.