"Nothing means as much to American swimmers as the Olympics."

It is a statement made by the United States Olympic women's swimming coach David Marsh and echoed by his athletes competing in the Games. 

It is also a rallying point for the US women, who head into the Games in something of a rut after the 2015 World Championship, when only the dominant Katie Ledecky and the 4x200 metre freestyle relay team managed to win gold medals. 

While Ledecky is expected to take home at least four gold medals in Rio, a handful of first-time Olympians will challenge Marsh to have his swimmers collectively ready for the big stage. 

Marsh, who has been a men's assistant coach in the three previous Olympic Games, is prepared, but experience does not equate to being the best in the world. 

"Looking at the global perspective of swimming, the biggest thing that [we] can [do] is appreciate what they're doing and how they are doing it," Marsh told Omnisport. 

"The Australian swimmers have come on very strong. It's wonderful watching the Campbell sisters.

"The European women have come on like gangbusters - Sarah Sjostrom from Sweden is going to be a factor and will bring relays up. The Danish are going to have a great medley relay. I don't think you can point to any one country - even the US - and say it's a slam dunk."

Ledecky, the world record holder in the 400 and 800m freestyles and the fastest woman in the 200m freestyle this year, could also be Marsh's go-to in each of the three relays. 

"We have the opportunity to see her widen her spectrum," Marsh said. 

"The more that she can focus on being her personal best, the more successful she can be.

"The big goal for us is to medal in all three relays and do whatever we can to push for the highest medal possible."

Australia, led by sprinters Cate and Bronte Campbell, will stand in the USA's way of owning the highest medal count, but Marsh knows even the favourites are vulnerable to upsets. 

"Mark my words, some of the swimmers who everyone thinks is going to win as the prohibitive favourite are going to be upset," Marsh said. 

"That's not unusual for the Olympics as the beautiful thing about our sport is it's one given day, one given moment. Some athletes will have multiple swims when others are going into their first and are more rested."

One of those upsets could come in the women's 200 and 400m individual medley at the hands of an American upstart. 

"Hungary's Katinka Hosszu is the clear favourite, but she's also been the clear favourite for four years running," Marsh said. "And when you do that, it can get hard to hold up that mantle all through the Olympics.

"The British have some good IMers, but Maya DiRado has really come along for us." 

Swimming at Rio 2016 gets underway on Saturday.