Ariarne Titmus has opened up on the pressure of entering the Paris Olympics as Australia’s face of the Games and her rivalry with Katie Ledecky after she was outlasted by the American legend in the 800m freestyle final.

Ledecky held off her long-time hunter and claimed her fourth consecutive gold medal in the event on Sunday morning (AWST).

Titmus swum just off the shoulder of Ledecky for 600 metres, conjuring Australian dreams off her power prevailing in the back end, but the indomitable Ledecky outlasted her closest rival.

The Tasmanian star defended her crown in the 400m freestyle in Australia’s highlight of the opening night, but was pipped by fast-emerging countrywoman Mollie O’Callaghan in the 100m final.

In perhaps the most emotional interview of her career, Titmus opened up on the weight of expectation she felt heading to Paris.

“This is the first time I’ve really let my emotions out. I felt so much pressure coming into these Games, just to hit my expectations, but I know a lot of people at home were willing and wanting me to win at these Games and defend my titles,” she said.

“To do it one day one makes me so proud and I can finally relax. It’s been a big week.

“We really feel it here (the support), it’s quite isolating. I’m looking forward to letting my hair down.

“I knew that at the end of eight days it would be tough, but I wanted to leave it all out there and go home from these Games with no regrets, I don’t think I’d be able to sleep at night if I second-guessed my approach to the race.

“I left it all out there and I am really proud of my efforts.”

Ledecky is now the first-ever woman to win four consecutive gold medals in the same event, a mark also reached by countryman Katie Ledecky.

She also steadied a wretched hour for the United States, where Alex Walsh was disqualified from the 200m individual medley and their athletes were mowed down in the 4x400m mixed relay and raging hot favourite Sha’Carri Richardson was pipped in the 100m on the Stade de France track.

Titmus finished with silver at the end of a jam-packed meet and said she hoped their bouts had made Ledecky a better swimmer as she paid tribute to one of the finest female athletes in history.

“She just has this incredible ability to sustain in a race,” Titmus said.

“The only way I could challenge her I thought was to take it up to her, but my body on the line, try and hang on.

“I’m proud of the way I put myself out there and took it to Katie, she’s just a champ and I have the most respect for her out of any athlete I have ever competed against.

“I know how hard it is to go back-to-back and be on top of the world in the same event for over 12 years is just remarkable.

“I feel so honoured to be part of her story and hopefully made her a better athlete as well.”

The 23-year-old leaves Paris with four career gold medals.

The swim was the 14th fastest of Ledecky’s career, while Titmus’ brave effort was a personal best and broke a national record. She is now just the second swimmer to penetrate Ledecky’s stronghold over the top-20 times in that event.

It was her first personal best in the event since the Tokyo Olympics three years ago.

Fellow Australian Lani Pallister sat in third for most of the first 400 metres, but impacted by a COVID diagnosis earlier in the week, fell away and finished in sixth.

American Paige Madden surged into contention after sitting in the middle of the field for the first 600 and claimed bronze. For about 100 metres, she loomed as Ledecky’s greatest challenge.