The 23-year-old Briton, who claimed her first major global medal on Monday, won her heat in 22.32 seconds.

Compatriots Jodie Williams and Beth Dobbin also reached Tuesday's semis.

Olympic champion Elaine Thompson also advanced, but former bronze medallist Blessing Okagbare was disqualified.

That disqualification, plus the withdrawal of 100m bronze medallist Marie-Josee Ta Lou, have boosted Asher-Smith's hopes in an event that was already without Dutch defending champion Dafne Schippers and 100m champion Shelly-Ann Fraser-Pryce of Jamaica.

Asher-Smith is ranked number one in this event this season and is the odds-on favourite to win her first global outdoor title.

'Dina is the favourite for 200m title'

It will take a special performance from her remaining rivals to take the gold away from Asher-Smith.

The Briton is now the only athlete from the top four in the London 2017 final still standing, with Bahamian bronze medallist Shaunae Miller-Uibo electing to run in the 400m at these championships.

Of those left, only Thompson has run faster than Asher-Smith this season. However, she came a disappointing fourth in the 100m final and was only seventh fastest in the 200m heats.

Britain's Sydney 2000 Olympic heptathlon champion Denise Lewis and former world and Olympic 200m and 400m champion Michael Johnson both believe it is Asher-Smith's title to lose.

"I just don't think there is anyone in the 200m field that can live with Dina right now," Lewis told BBC Sport.

"She doesn't want to think about the 100m. She has moved on. It's all about the recovery now.

"She has had to come out here again and produce. Women don't take chances, there was no showboating."

Johnson added: "What we can take from this is that Dina is the favourite with all the others dropping out.

"Thompson doesn't look herself and you have to start looking at the race behind Dina."