Only in the final lap did the man who holds the world record of 26:11.00 move into top gear to take on and then dismiss the challenge of the Ethiopian who beat him to Olympic gold at this distance last summer, Selemon Barega.

After his team-mates Stephen Kissa, who eventually finished 24^th and last, and Jacob Kiplimo, who eventually added a bronze to the one he won in Tokyo last summer, had ensured the pace throughout was brisk without being extravagant, Cheptegei found himself perfectly placed to claim another global gold.

When the bell went the presence of two Americans in a group of seven medal contenders meant the noise levels rose to the heights, and around the final bend Cheptegei and Barega appeared to be contesting the gold.

Down the final straight, however, the Ugandan proved unchallengeable and the Ethiopian eventually slipped back to fifth place as three runners came past him.

The first was the relatively unknown 22-year-old Kenyan, Stanley Mburu, who fell early in the opening lap and almost went down again a few laps later, but still had enough to earn unexpected silver in 27:27.90.

Kiplimo had enough of a finish to take third place in 27:27.97, with fast-finishing home runner Grant Fisher passing Barega a couple of metres before the line to place fourth in 27:28.14, with Barega clocking 27:28.39.

While Barega was unable to fly the Ethiopian flag on the track, his compatriot Tamirat Tola was more successful earlier in the day as he won the men’s marathon in a Championship record of 2hr 05min 36sec.

The world marathon silver medallist of 2017 became the world marathon gold medallist of 2022 after a masterful and ruthless run over three laps of a looped 14km course through Eugene and Springfield which saw him come home more than a minute clear.

Tola made his move between the 33^rd and 34^th kilometre of this 42.195km event, drawing inexorably clear of the field.

His team-mate Mosinet Geremew won a protracted battle for silver, pulling clear of Tokyo 2020 bronze medallist Bashir Abdi over the final kilometre to finish in 2:06.44, with the Belgian taking another big bronze in 2:06.48.

Missing the medal podium by one place was the unlikely figure of Canada’s Cameron Levins, who had the consolation of setting a national record of 2:07:09 ahead of Kenya’s three-times World Half Marathon champion Geoffrey Kamworor, who clocked 2:07:14.

"It was a dream come true," said Tola, who took more than a minute off the record of 2:06.54 set by Kenya’s Abel Kirui at the 2009 edition in Berlin.

"I learned from my mistake in 2017 (World Championships) and I made sure it did not happen again."

On that occasion Tola’s attempted run for home 10km from the end was thwarted as Kenya’s Geoffrey Kirui overtook him to win gold. 

This time there was no faltering on the 30-year-old Ethiopian’s part.

Home athlete Brooke Andersen stood up for herself in the women’s hammer throw final en route to what turned out to be an emphatic victory.

After Canada’s Camryn Rogers had taken the lead off her with a third round effort of 75.52m, Andersen appeared to have responded in ideal fashion, but her effort was initially ruled out for what could have been a foot moving out of the circle.

However the 26-year-old Pan American silver medallist of 2019 queried the judges’ decision and succeeded in having her throw measured - it was 77.42m and she was back into a lead she would not let go again.

Andersen improved to 77.56m in the fifth round, and after Rogers had failed to improve on her sixth attempt she arrived in the circle as world champion - and signed off with a further improvement, to 78.96m, just shy of her personal best of 79.02m.

Meanwhile, after the first three events of the heptathlon, Belgium’s double Olympic champion Nafissatou Thiam is moving with stupendous speed, height and power to regaining the world title she earned in London five years ago.

The 27-year-old from Brussels laid down a marker by producing a personal best of 13.21sec in the opening 100m hurdles, where she finished fifth best, before moving to the event where she stands almost literally head and shoulders above her multi-event rivals, the high jump, where she has a best of 2.02m.

A clearance of 1.95m was enough to win her the event and take her into the overall lead, which is where she remained after the third event of the morning session, the shot put.

Despite rumours of an injured elbow she threw the shot out to 15.03m to take second place in the event and boost her overall total to 3127 points with the 200 metres still to come later on the first day.

Anouk Vetter of The Netherlands is second on 3003, and Adrianna Sulek of Poland third on 2979.

Meanwhile Britain’s defending champion Katarina Johnson-Thompson, who suffered a ruptured Achilles tendon in 2020 and was stricken by a hamstring injury at the Tokyo Olympics last summer, worked diligently to get back into something like her form of old and went into the second session in seventh place with 2781.