Christine Ohuruogu looks in the form of her career but will not be taking her 400 metres rivals for granted in the World Championship final.
The 29-year-old has been superb in Moscow, following up a comfortable heats victory with a similarly impressive semi-final win.
Ohuruogu crossed the line in a season's best time of 49.75 seconds despite easing down at the finish and looks set to threaten Kathy Cook's 29-year-old British record of 49.43.
"I'm just really happy to be in the final," she said. "I wanted to make sure I finished well at the end."
The 2007 world champion gave little away as she marched through the media zone, although her coach Lloyd Cowan was more forthcoming.
"All I asked her to do was to execute her race really well," he said.
"There is a point when all I need her to do is get the very simple things right and then she'll be fine.
"We absolutely can't take anything for granted tomorrow - there are six girls inside 50 seconds and most of them are going to be even closer to the line in the final.
"At the end of the day I'll just be happy if she puts together a great race tomorrow, that's all I want."
Ohuruogu is the star of Monday's action, but there are plenty of other British athletes on display.
Reigning 400m hurdles world champion Dai Greene kicks off his title defence in the heats, where he is joined by compatriots Rhys Williams and Sebastian Rodger.
Meghan Beesley and Elidh Child are also set to start their 400m hurdles campaign, as is Perri Shakes-Drayton.
The 24-year-old Londoner clocked her fastest time outside a major championship at last month's Anniversary Games and is looking to build on her 53.67s time in Moscow.
"People have expectations, and I have expectations of myself, but I don't see it as pressure," the year's third fastest woman said.
"This is nothing like the Olympics, it's not in my back yard."
Elsewhere, William Sharman, Asha Philip and Nigel Levine are gunning for places in their respective finals.
Discus thrower Brett Morse and heptathlete Katarina Johnson-Thompson got their campaigns under way, while James Wilkinson was going in the 3,000m steeplechase.