Great Britain's Hannah Cockroft became the first athlete to break a world record at the Olympic Stadium.
The 19-year-old picked up bronze in the women's 100m multi-classification final of the Visa London Disability Athletics Challenge, which forms part of the testing programme for London 2012.
Despite finishing in third place, Cockroft's time of 18.56 seconds saw her lead the way in the T34 class and break the world record.
"I just wasn't expecting that," she said. "What can you say? That's history made.
"It just came out of nowhere. I raced on Sunday and wasn't expecting much today.
"I was a bit apprehensive before the race and then that happens. I just don't know what to say."
Cockroft's record-winning performance was made all the more impressive by her heavily-disrupted preparations for the race.
"We were running three or four hours behind schedule because of a coach crash on the way here," she said.
"So I missed my call up, I missed my warm-up. I had to literally go straight on to the track.
"It's not exactly the best preparation, so hopefully I can break the record by a lot more than that.
"I wasn't prepared at all today but it was a great performance."
Ireland's Michael McKillop became the first male athlete to set a world record at the Olympic Stadium less than half an hour later.
The Antrim athlete led home the field in the multi-classification 1,500m final, with his time of three minutes 59.54 seconds beating his previous world best T37 time by 15 seconds.
"It was incredible and enjoyable and an experience I wanted to get out of my system," said the reigning 800m Paralympic gold medallist.
"It's one of those things - you want to walk into a stadium for the Paralympic final without worrying or thinking 'oh my god' the stadium is huge or the track bigger."
Britain's Paul Blake competed in the same race and was also able to celebrate a world record, with his time of four minutes 34.42 seconds a new best for the T36 1,500m.
Richard Whitehead became the fourth and final world record-breaking athlete of the day, cutting his own 200m T42 world best time to 25.50 seconds.
"The whole atmosphere here today was great," he said.
"It's an important day for GB athletes to gain confidence and a little bit of success under the spotlight.
"I said I'd do 25.5-dead and I did. That's what I wanted to do.
"I wanted to set a marker. Hopefully, this will go around the world and can tell certain other athletes that they need to step up if they want to challenge me."