London - Australian hurdling great Sally Pearson's impressive comeback from two years of injury hell continued on Friday as she posted the fastest time in reaching Saturday's 100m hurdles world final.
The 30-year-old's sublime run contrasted sharply with America's world record holder Kendra Harrison who squeaked into the final as the slowest of the two fastest losers who qualify.
Harrison - who was the 1/6 on favourite for the title and had not been beaten in a race since the US Olympic trials last year - at least made it unlike Jamaica's defending champion Danielle Williams who flopped to finish fifth in her semi.
Pearson looked tense and focused before the race, not acknowledging the crowd when her name was called, but was hugely impressive quickly overhauling early leader Jamaican champion Megan Simmonds and opening a sizeable lead.
The race was over as a contest as Pearson hurdled impeccably to hit the line in 12.53 seconds a broad grin spreading across her face and then clenched her fists in celebration.
"I haven't come here to come second," said Pearson.
"I'm just happy to be going through the rounds and feeling good; it's a matter of doing it to my own art."
Pearson said that despite suffering a bone explosion in her wrist in 2015 - which she feared was so bad it would result in having her hand amputated - and then a hamstring injury last year which robbed her of the chance to defend her Olympic title she had never lost her hunger for the sport.
"I've always loved what I do, and I've always been motivated," she said.
"I think it's just a matter of wanting to know that I have more to give - and I do."
Olympic silver medalist Nia Ali of the United States took the second automatic qualifying spot.
Harrison's problems started as she hit the first hurdle and dropped to seventh and it was only her determination and class that saw her get back into contention to fight her way back to third and just make the final.
"Unfortunately I hit the first hurdle and I just had to readjust. I had to tell myself not to panic because I've done the training," said the 25-year-old.
"I've run the world record in this stadium so I was capable of making up for the error. I didn't hurt myself so I'm fine.
"I can't worry about one performance. I've done a lot of work so I have to trust that."
Victory went to her veteran compatriot Dawn Harper-Nelson, the 33-year-old 2008 Olympic champion who celebrated with a spectacular cartwheel.
Another American Christine Manning produced a faultless display in her semi to progress in 12.71 seconds but the opposite was the case of Williams who hit the first hurdle and unlike Harrison never recovered her composure.