“I’m so excited to get that ‘A’ time on my first chance in a World Championship trials,” said McCartney.

“I’ve really been aiming for that time. Me and my coach, since the start of this year we knew it was doable, but I never thought I’d be that far under it.

“I don’t like setting my expectations too high. I prefer to trust the process and I have days where I think I can do it, I have days where I’m like, what if I just miss out, but I just wanted to make sure I left everything in the pool and that’s when I can be happy and to be this far under, it’s mind-blowing for me.”

McCartney also has qualification times for the European under-23s, and the World University Games and she’ll now have to plan out a summer with the worlds included, so it’s likely she will have to choose only one of the first two events.

She joins Ulster swimmers Daniel Wiffen and Danielle Hill as well as Mona McSharry, Ellen Walshe, Tom Fannon and John Shortt as those with the consideration times for Ireland for the event in Singapore.

“It’s been years since I’ve been able to race Mona and to be closer, I’ve never had that chance before and racing her is always such a privilege and seeing the likes of Jack McMillan, Daniel, Danielle and Mona all coming from similar routes, it’s inspiring”, she added.

“It’s what makes me want to be better.”