The 24-year-old Dubliner will go to the line at 2.05pm Irish time for the medal decider – her first ever global outdoor final.

Healy snuck into the final following a disqualification of a rival, having crossed the line seventh in her semi-final, but with a stronger pace expected here she should find this kind of race more to her liking.

Faith Kipyegon should prove unstoppable in her bid for a seventh global 1500m title, while for Healy a top-eight finish looks within reach and would cap a season of remarkable consistency.

Just after midday Irish time, Cian McPhillips and Mark English will race the heats of the men’s 800m, both needing a top-three finish to automatically advance.

English should have little trouble securing that, despite being drawn alongside Olympic champion Emmanuel Wanyonyi, though McPhillips might face a trickier task, and anyone who fails to make the top three could face a swift exit, with just three additional time qualifier spots across the seven heats.

Sharlene Mawdsley is drawn in lane three for her semi-final of the women’s 400m at 1.23pm Irish time.

Just the top two will automatically advance, with two additional time qualifiers across the semi-finals.

The Tipperary sprinter is unlikely to challenge for those, with four women in the field who have run below 50 seconds – among them US superstar Sydney McLaughlin-Levrone.

Mawdsley will look to improve her season’s best of 50.93 and challenge her personal best of 50.71. Regardless of her finishing position, she’ll be able to hold her head high having reached this point.

In addition to the women’s 1500m, the men’s hammer, men’s high jump and men’s 110m hurdles will all be decided today.

The Japanese crowd will raise the roof if their star sprint hurdler, Rachid Muratake, can power to gold in the climactic event.

World Athletics Championships, Tokyo – Live, RTÉ Two, 11.15am; BBC Two, 11am

Irish in action, Tuesday (all times Irish)

12.02pm: Cian McPhillips, men’s 800m heats

12.12pm: Mark English, men’s 800m heats

1.23pm: Sharlene Mawdsley, women’s 400m semi-finals

2.05pm: Sarah Healy, women’s 1500m final