There was no hiding the shock as she touched the wall, and looked up to see 16min 27.34sec shining from the screen, though.
The time was an 8sec personal best for the Neptune swimmer and also an A-standard qualifier for the Fina world championships in Budapest in July.
It left her 30sec ahead of her nearest rival in the race secure gold in the women’s 1500m freestyle, as the national swimming championships finished in Auckland on Saturday.
"It was more just disbelief, really, at the start, that I’d actually done it," Deans (22) said.
"It’s been a goal of mine for a while now to be under that Fina A standard. Then not qualifying for Tokyo, it’s been a goal for a while now.
"Actually achieving it, it was disbelief."
Her time lifted her to sixth on the all-time New Zealand rankings in the event, as well as placing her 10th in the world this year.
New Zealand’s team for Budapest will be confirmed in the next week, although the A standard makes it is likely Deans will be among those named.
She will also compete on the Mare Nostrum tour around southern Europe before the world championships, leaving on May 13.
The international racing was something she was looking forward to, having not done much of it since the beginning of the pandemic.
While she had hoped the Tokyo Olympics would have broken that drought, Deans felt she had learned some key lessons from the experience of trying to get there.
"My biggest one is backing my training and backing myself in racing," she said.
"It’s something I’ve always struggled with. I’ve had a really good team at home, with my coaches and athlete life adviser Nat Fraser.
"They’ve really worked on my confidence and just knowing, with the training I’ve done, that I am capable of putting together the race on the day."
She joins fellow Neptune swimmer Erika Fairweather in qualifying for the world event.
Kiwi’s Kale Twist also achieved a qualifying mark for the Pan-Pacific junior championships in Honolulu.
His time of 23.53sec set an Otago open and 17-years record in the men’s 50m freestyle, while placing him fifth.
Neptune’s Esme Patterson took 3sec off her personal best to claim silver in the women’s 200m butterfly, clocking a time of 2min 17.94sec.
Ruby Heath (Neptune) won Otago’s other medal, a bronze in the same 1500m race Deans won.
