Sophie Hitchon improved her own British record on the way to qualifying for the London 2012 women's hammer final.
Hitchon was set to bow out after a first-round attempt of 67.21m and a foul in the second, but the 21-year-old then produced a superb throw of 71.98m in the final round, 37cm further than her previous best.
That was still short of the automatic qualifying distance of 73m, but good enough for fifth overall in Group A with 12 athletes across both qualifying groups advancing to the final.
Hitchon was delighted with her British record, adding: "I was just proud to be on the team and to come here at a morning session, with a full crowd and throw a PB and a British record, it was amazing.
"I did the same at the Europeans (leaving it to the last throw) and I don't know why. I like to put a lot of pressure on myself for some reason. I knew it was there, I've been throwing really well in training. I was ready and obviously it showed.
"I've never competed in front of a massive crowd like this and 90% of the whole crowd is cheering for you. Everyone just wants you to do really well."
The former ballet dancer finished 10th overall after the conclusion of Group B.
And fellow British record holder Steve Lewis also advanced to the pole vault final with just one vault, a first-time clearance of 5.50m enough for the 26-year-old to go through as one of the 14 qualifiers.