Over the past two days, a common sight was Shane Tusup, coach of Hungary's triple Olympic champion Katinka Hosszu, pacing around the pool deck at the OCBC Aquatic Centre with brows furrowed, voice booming and wearing an expression that basically tells you to "get lost".
The intensity of Tusup, a former college swimmer, could be seen in the way he admonished anyone who he thought could affect Hosszu's performance at the Fina/airweave Swimming World Cup - venue staff, officials and public relations folks pleading for a stop at the mixed zone.
Speaking to The Sunday Times yesterday, Tusup made no excuses for his behaviour - not least l because Hosszu is his wife.
Finally looking more relaxed after all the racing was over, he said: "I just want what is best for her. I'm only saying what I think is best for her. We have to balance (the relationship) very delicately but we both trust each other. It's one team, one goal.
"If she wants to quit tomorrow, I'm out. I'm done. I only want to help her."
The public first saw this side of Tusup during the Rio de Janeiro Olympics, when the American was a one-man sideshow in the stands - bellowing instructions, fist pumping, veins bulging on his left bicep, with a tattoo of Hosszu's "Iron Lady" moniker.
HIS VIEW OF HER
I just want what is best for her. I'm only saying what I think is best for her. We have to balance (the relationship) very delicately but we both trust each other. It's one team, one goal.
SHANE TUSUP, on coaching and managing his swimmer wife Katinka Hosszu.
HER VIEW OF HIM
He's actually really sweet at home. He's definitely more chill. I wear the pants at home. Look, swimming is what we put our lives into, it's our passion, so of course we're going to show emotions.
KATINKA HOSSZU, on her relationship with Tusup.
But other swimmers, including Hosszu's former training partner Jessica Hardy, have spoken out against Tusup's aggression, and questioned if their relationship was healthy.
Laughing, Hosszu confirmed her husband is a completely different person away from the pool.
"He's actually really sweet at home. He's definitely more chill. I wear the pants at home," she said.
"Look, swimming is what we put our lives into, it's our passion, so of course we're going to show emotions."
Tusup, who first met Hosszu when they were studying at the University of Southern California in 2008, said: "It's sports, I'm like that when LeBron James plays too. Swimming has a culture of being quiet, reserved, at least among the coaches.
"You see (Golden State Warriors coach) Steve Kerr breaking the clipboard in the (NBA) Finals. It's the same thing. There are a lot of emotions, especially when I'm her husband as well."
He started coaching her after the 2012 London Olympics and they were married a year later.
On all the brickbats they had to endure, she said: "I think we made our statement in the pool."
They certainly made a resounding one. Since Tusup started coaching her, Hosszu has gone from strength to strength, winning and retaining the 200m and 400m individual medley golds at the biennial world championships.
Tusup said while they have made tweaks to her technique and fitness regimen, the key was getting his wife to believe that she is, well, great.
"When it comes down to it, you got to trust that the hard work will come out. The difference in London was she didn't trust herself when she was sitting on the blocks."
Their partnership flourished in Rio, when Hosszu, who had finished empty-handed at three Olympics, won golds in both medleys and the 100m backstroke, as well as as silver in the 200m back.
She also set a new world record in the 400m medley.
"Achieving it together, it's just that much better to celebrate, because he knows exactly what I have to go through to get there," said Hosszu.
"It's really special and we are definitely going to remember every moment for the rest of our lives."
Life has changed since Rio.
Now, Hosszu cannot roam the streets of Budapest without being mobbed. Now, she has unimaginable expectations on her shoulders as she bids to retain her titles at the world championships on home turf next July.
"I realise Hungarians care a lot more about the Olympics," she mused.
Come what may, the Iron Lady can at least count on her Man of Steel relentlessly willing her on.