Olympian Tyler Butterfield and Kristyn Tobey-Robinson claimed the men's and women's titles at the Tokio Millennium Re Triathlon in Hamilton.Butterfield covered the 750 metre swim, 20k bike and 5k run in a combined time of 56 minutes and 15 seconds."Today I went pretty hard and didn't mess around, it was training for London," said Butterfield, making his first appearance on local shores in nearly two years. "Jonathan Herring (1:01.23) and Neil De Ste Croix (1:03.23) rounded off the top three in the men's field.Robinson successfully defended her women's crown after covering the race course in 1:07.38."I was pleased with my performance," Robinson said. "It was definitely warm, I could even feel it on the bike and heading into the run."So it was nice that it was a short sprint today and not anything longer because it's hot."Laurie Orchard (1:11.03) and Emma O'Connell (1:13.24) finished second and third respectively.