The 20-year-old looked in fantastic form as she reduced her own women’s 200m individual medley British record to 2:07.57 to qualify fastest overall for the final, taking place at 3.29am BST.
“I thought I could do it but it’s been a long time coming – my last PB was at the Commonwealth Games two years ago. I thought I had it in me last year but it didn’t quite go to plan, so to finally break the 2:08 is great.
“It’s a bit of a shock to be fastest but people have had other races. The final is a completely different ball game. I’ve just got to do my best, recover well and relax. I know I’m swimming well so I’ll just do my best tomorrow and see what happens.”
O’Connor, who first started training in the University of Bath swimming pool aged nine with the former Team Bath Futures squad, won a bronze medal at last year’s World Championships in the IM.
Her impressive performances in the Aquatics Centre – she was also second-fastest in the heats – came the day after Adam Peaty and training partner Carlin had won 100m breakstroke gold and 400m freestyle silver respectively.
“Last night was amazing,” said O’Connor, making her second Olympic appearance for Team GB having also competed at London 2012.
“I was absolutely gutted because I had to stay at the hotel to relax and prepare for today but I was so buzzing watching it. I was in tears watching Adam and Jazz – they’re so inspiring and it was an incredible night.”
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