The American swimmer clocked 4min 06.45sec at the Aquatics Centre in Chile's capital, shaving almost two seconds off the previous record set by Canada’s Emily Overholt at Toronto 2015.

She saw off the Brazilian challenge of Maria Fernanda Costa and Gabrielle Roncatto who finished in 4:06.68 and 4:06.88, respectively, for the other two podium spots.

Madden’s victory  set the ball rolling for the US as they went on to claim three more swimming gold medals on the opening night.

Dakota Luther emerged victorious from the women’s 200m butterfly final in 2:09.97, while Mason Laur won the men’s 200m butterfly title in 1:56.44.

There was an American one-two in the men’s 100m breaststroke final as Jacob Foster overcame Noah Nichols to triumph in 59.99sec.

Guilherme Costa of Brazil produced a Games-record time of 3:46.79 to win men’s 400m freestyle gold.

Brazil also came out on top in the men’s 4x100m freestyle relay final, seeing off the US and Canada to win in 3:13.51.

The women’s 100m breaststroke final saw Canada’s Rachel Nicol triumph in 1:07.28 as compatriot Sophie Angus had to settle for silver in 1:07.55.

Reigning Olympic women’s 100m butterfly champion Maggie Mac Neil helped Canada capture the women’s 4x100m freestyle relay crown in 3:37.75.

Staying in the pool, Mexico secured the first two golds on the opening day of diving competition in Santiago.

Two-time world silver medallist Osmar Olvera clinched men’s 1m springboard gold with a score of 424.70 points.

Jonathan Ruvalcaba of the Dominican Republic bagged silver with 384.90, while Colombia’s Luis Uribe earned 371.20 for bronze.

Mexico picked up two women’s 10m platform medals as Gabriela Agúndez sealed gold with 361.55 to beat compatriot Alejandra Orozco who finished with 340.80.

Canada’s Caeli McKay completed the podium when she bagged bronze with 335.65.

There was joy for both Mexico and the US on the shooting range at the Polígono de Tiro de Pudahuel.

American Sagen Maddalena secured the first shooting gold with victory in the women’s 10m air rifle final with a score of 249.5 before Edson Ramírez delivered the men’s 10m air rifle title for Mexico with 245.5.

The artistic gymnastics men’s team all-around title went to the US made up of Cameron Bock, Stephen Nedoroscik, Curran Phillips, Colt Walker and Donnell Whittenburg.

The US top scored with 249.860 after 41.232 points on floor, 39.799 on pommel horse, 41.666 on rings, 43.599 on vault, 42.665 on parallel bars and 40.899 on horizontal bar.

Canada came second with 246.794 points, while Brazil scored 245.394 for bronze.

In weightlifting, Cuba’s Arley Calderón won men’s 61 kilograms gold, Venezuela’s Julio Mayora claimed the men’s 73kg title and Dahiana Ortiz of the Dominican Republic captured the women’s 49kg crown.

Mexico and the US shared the gold medals as taekwondo competition got underway at the Contact Sports Centre.

William Arroyo won the first of Mexico’s three golds when he defeated Nicaragua’s Elian Ortega to win the men’s individual poomsae title.

This was followed by golds for Brandon Plaza and Daniela Souza for Mexico in the respective men’s 58kg and women’s 49kg categories.

American Kaitlyn Reclusado secured the women’s individual poomsae gold after overcoming Maria Higueros, competing under a neutral flag due to the suspension of the National Olympic Committee of Guatemala.

Khaifani Harris was the other US gold medallist courtesy of his victory in the men’s 68kg final against Bernardo Pie of the Dominican Republic.

Competition is due to continue in tomorrow with medals set to be awarded in athletics, BMX racing, road cycling, diving, artistic gymnastics, shooting, skateboarding, sport climbing, swimming, taekwondo and weightlifting.