Last year in Tokyo Cheptegei kept his powder dry until the bell, only to be outkicked by Selemon Barega. On Sunday he started upping the ante with over a kilometre to go, throwing in laps of 64 and 63 seconds to stretch a group of eight as they hit the bell.
"I knew that if I get into the last fight, I can control it and I could speed it up," said Cheptegei, still only 25 but who made his world championship debut back in 2015. Fast-finishing Grant Fisher just ran out of track in his bid to win a first medal in the event for the United States, finishing fourth, with Ethiopia's Olympic champion Barega unable to repeat his Tokyo fireworks as he ended up fifth.