The American, who won team gold medals at both Athens 2004 and Beijing 2008, excelled with two clear rounds at the CenturyLink Center, while riding HH Azur.

"I’ve been doing this for 25 years or more, and I've come so close so many times and one way or another I’ve messed it up," said the 41-year-old. 

"I'm so grateful for my horses and the people around me like my groom. 

"They all helped me pull this off."

Ward, who won an Olympic team silver medal at Rio 2016 in August, has become the 10th American to win the World Cup title.

"I've been in this situation where I've cracked, so I took a breath and believed in my horse - and she did it," he said.

Switzerland's Romain Duguet put pressure on Ward while riding Twentytwo des Biches, but had to settle for second place on four faults.

Henrik von Eckermann of Sweden rode Mary Lou to third place, recording eight faults.