New Zealand middle distance great Nick Willis has missed a medal at an athletics world championships for the sixth successive time.

Willis was forced to settle for eighth place in a 1500m final dominated by Kenyan athletes.

Elijah Manangoi won in a relatively slow time from Timothy Cheruiyot, with Norway's Filip Ingebrigtsen third.

Willis was too far back to threaten but looked strong in the home straight, surging past three-time world champion Asbel Kiprop of Kenya to clock three minutes 36.82 seconds.

Double Olympic medallist Willis ran in typical style near the tail of the field but that tactic backfired when a trio of Kenyans upped the pace in the second lap following a passive start to the race.

The 34-year-old Kiwi was trapped among the back-markers and in no position to attack over the last 400m.

Willis has never won a world championships medal in six attempts. His best performance came two years ago when placing sixth in Beijing.

Chronic shin splints which curtailed the start to his competitive season left him doubting his ability to peak at the year's biggest meet.

His time on Monday (NZT) was more than 2sec outside his season's best and more than 7sec slower than his personal best, set in 2015.

Earlier, Quentin Rew secured a place in the New Zealand record books with an expertly-timed performance in the 50km walk.

Rew surged home 12th, clocking a national record three hours 46 minutes 29 seconds.

It was more than 2min quicker than Rio Olympian Rew had walked before and eclipsed Craig Barrett's 16-year-old former national mark by 1min 34sec.

Rew was 29th after the first 5km but spent the rest of the race making up places. He climbed six spots over the last 5km as his rivals faded in hot conditions.

"The race for me was just putting myself in a good position so that when people did come back I could take advantage of that and go past them," he said.

Rew was more than 13min behind winner Yohann Diniz, who made championship history.

At 39, the Frenchman became the oldest male to win a gold medal in any event.