The 18-year-old Summer McIntosh has made it three world records in less than a week by breaking her own 400-meter individual medley mark at the Canadian swimming trials.

McIntosh came within a whisker of breaking a third world record at the Canadian swimming trials on Tuesday after finishing 0.45 seconds outside Liu Zige's 200m butterfly mark set during the era of the now-banned "super-suits".

McIntosh won the women's 200-metre butterfly final in a Canadian record time of 2:02.26 on Day 4 of national trials on Tuesday, completing the second-best performance in the history of the event.