There's tough love.
And then there's what coach Dean Boxall provides to Australian swimming's rising star Ariarne Titmus.
But it seems to be working.
Teenager "Arnie" Titmus - dubbed The Terminator by her dad - again showed her killer instinct to back up from her shock 200m freestyle win and defend her 400m national title at the Gold Coast Commonwealth Games swim trials on Thursday night.
She clocked four minutes, 02.36 seconds to win by more than five seconds and eclipse her own Australian record set in December.
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Booking her second event for the Games in as many nights, the 17-year-old Titmus showed no mercy to the 400m field - much like her coach Boxall's approach pool-side.
"Some of the things he says aren't quite appropriate (to share publicly)," Brisbane-based Tasmanian Titmus laughed.
"But he always says if I get better he has to push harder, so it's been tough.
"I keep my ground I think but he pushes me harder than anyone else in the (Brisbane club St Peters Western) squad.
"He is always on my back. There is never a moment I can relax - I always have to be on.
"But he's just being Dean."
One of the raw nerves Boxall likes to poke is Titmus' 400m freestyle fourth placing on international debut at the 2017 world titles.
After only making her junior national team debut earlier that year, Titmus announced herself as a world force by just missing a 400m medal behind American great Katie Ledecky.
Boxall didn't seem too impressed though.
"At the end of training he says 'if you do this time you get the gold, if not you get fourth'," Titmus said.
"He pushes my buttons sometimes. A lot of people couldn't handle it but it keeps me mentally tough for racing.
"I know he is only trying to help me and that he believes in me so much."
That toughness showed when she upset Olympic bronze medallist Emma McKeon in the 200m medal race in the trials' first major boilover on Wednesday's opening night.
Now she has a rare 200m-400m-800m national sweep in her sights.
"Dean was saying it has been a long time since someone has won the 200m, 400m, and 800m at a national championship - it's real exciting," Titmus said.
