The Brisbane-born 19-year old who counts O’Niell as one of her role models this week swam the fastest time for the race in the country, and now holds the new national record of 2 minutes 5.41 seconds.
O’Niell broke the world record and moved her ranking to number one when she swam a 2 minute 5.81 second race in May, 2000 at the Australian Open Swimming Championships in Sydney.
"I can’t believe I went under Susie’s time," Groves said on Monday night at the trials for the Australian Swim Team.
The 19-year-old is now training with Stephanie Rice’s former trainer, Michael Bohl.
Groves who has a love of sushi and iced coffee - according to her Swimming Australia profile - has made a strong return to the pool, winning the 2013 and 2014 National Champion in the 200 metre butterfly and gaining selection into the 2014 Commonwealth Games Team.
But niggling back and shoulder pain have held Groves back in the past year as she suffered in the Commonwealth Games, picking up a bronze in the women's 200 metre butterfly.
The problem was solved by her gym coach, Chris Miller, who worked out the swimmer was clenching her jaw which a trip to the dentist and teeth caps have ‘miraculously’ fixed, according to The Australian.
And with a new record on Monday night, it’s seems to have worked wonders.
"Her 100 fly is very good but I think the 200 fly is the event," Bohl told News Corp in 2014.
"It would be nice to see her do well in both but I think 200 fly is the special one for her."
Bohl was certainly on the money, as Madame Butterfly 2.0 has just made her debut.