Saturday, 3 March 2018:

KAYLEE MCKEOWN gives a smile after winning the final of the Women's 200m Backstroke event during the 2018 Australia Swimming National Trials at the Optus Aquatic Centre in Gold Coast, Australia.

Her family went nuts in the stands as teenager Kaylee McKeown pulled off a huge upset over dual world champion Emily Seebohm to claim 200m backstroke gold at the Gold Coast Commonwealth Games swim trials.

But it was another loved one to whom 16-year-old McKeown dedicated her maiden national title at Gold Coast Aquatic Centre on Friday night.

Despite getting tangled up in the lane ropes in the final 50m, McKeown still clocked two minutes, 08.23 seconds to down Seebohm by just 0.01 of a second.

Ecstatic family members including her sister Taylor - the defending Commonwealth 200m breaststroke champion - were captured by TV cameras cutting loose in the stands as McKeown pulled off the stirring win.

Yet McKeown's thoughts were with her ill grandfather Joe after announcing herself as a Games threat.

"I didn't want to swim the race for myself, my grandad is not too well at the moment, so I put all my effort in for him," an emotional McKeown said.

"It's good to do that for him."

Remarkably McKeown's 200m gold marked the third time this season that the teenager had toppled Seebohm after emerging triumphant at the Queensland and Victorian state titles.

Not that she knew at the time.

McKeown said she couldn't see the results on the big screen from the pool and wanted to avoid the potentially awkward situation of asking two-time national champ Seebohm whether she had beaten her.

"I actually didn't see my time because the board's a long way away and I don't have the best eyesight," McKeown said.

"And I didn't want to ask Em (Seebohm), so I had to wait for it to come up on the board behind us.

"Earlier in the 100m backstroke final I did the same thing and had to ask someone how I had gone - it was a little bit embarrassing."

McKeown finished third in the 100m backstroke on Wednesday night to earn her first individual Games berth.

Big things were expected of McKeown after she burst onto the international scene with a 200m backstroke fourth placing in a new junior world record on world titles senior debut last year in Budapest.

Yet no one was quite prepared for McKeown to knock over world champ Seebohm on Friday night.

Still, Seebohm seemed the least surprised by her training partner McKeown's heroics at Gold Coast Aquatic Centre.

"She was always going to be a good challenger because of what she did at worlds - she is going to keep me on my toes," she said.

AAP