Summer McIntosh dominates 400m IM as records fall across night two at Pan Pacs

Summer McIntosh led the 400m individual medley from start to finish at the Pan Pacific Championships in Irvine, California, winning in a championship-record 4:28.01 on 14 August 2026. The Canadian, Olympic champion in the event from Paris 2024, was never challenged — Australia's Jenna Forrester took silver in 4:31.50, more than three seconds back. Bronze went to Argentina's 18-year-old Agostina Hein. The Guardian

Forrester had opened the second night of finals with that silver swim, according to Swimming Australia's Dolphins social media accounts. McIntosh's victory followed a runner-up finish behind Australia's Lani Pallister in the 200m freestyle on the opening night, a result confirmed by Reuters.

The individual medley — swimming butterfly, backstroke, breaststroke and freestyle in that order, over 100 metres of each stroke — rewards versatility and stamina. McIntosh's time was a Pan Pacs mark, not a personal best; she swam 4:11.32 at the Canadian Trials in July, one of the fastest times ever recorded in the event.

The night produced championship records across several events. Australia's women's 4x200m freestyle relay team of Inez Miller, Lani Pallister, Hannah Casey and Milla Jansen won in 7:42.40, lowering their country's own championship standard of 7:44.12 from the 2018 Pan Pacs. The United States — with Erin Gemmell, Anna Peplowski, Rylee Erisman and Katie Ledecky — also went under the old mark for silver in 7:43.10. Ledecky swam the anchor leg but could not run down Jansen. Canada, with McIntosh, took bronze.

The men's 4x200m freestyle relay saw another championship record: Luke Hobson, Aaron Shackell, Patrick Sammon and Gabriel Jett of the United States led the entire race to win in 6:59.37.

In the sprint events, Meg Harris of Australia won the women's 100m freestyle from lane six in 52.60 seconds. American Gretchen Walsh, second in 52.78, had been 0.01 seconds under world-record pace at the turn before fading. Olivia Wunsch of Australia was third. Simone Manuel, the 2016 Olympic champion, finished fourth.

Jack Alexy of the United States won the men's 100m freestyle in 47.14 seconds, lowering his own championship record of 47.40 from the preliminaries. Patrick Sammon made it a US 1-2, with Brazil's Guilherme Caribe third.

McKenzie Siroky of the United States won the women's 100m breaststroke in 1:05.32 for her first international medal, edging China's Tang Qianting, who clocked 1:05.46. Van Mathias took the men's 100m breaststroke in 58.02 seconds — his third medal of the meet — lowering his own championship record from the heats.

In the 50m backstroke events, Quintin McCarty won the men's race in 24.51 seconds, beating the championship record that Isaac Cooper of Australia had set in the preliminaries. Katharine Berkoff won the women's race in a career-best 26.90 seconds, bettering her own championship mark also set in the heats. Regan Smith was second in 27.14.

Japan's Tomoyuki Matsushita won the men's 400m individual medley in 4:06.75, erasing a championship record that had stood since 2010 — American Ryan Lochte's 4:07.59 from the Pan Pacs in Irvine sixteen years ago.

The United States also won the mixed 4x100m medley relay (two men, two women) in 3:36.70 with Will Modglin, Van Mathias, Gretchen Walsh and Kate Douglass, bettering the previous championship record. Reuters

For fans tracking the road to Los Angeles 2028, the Pan Pacs offer a first look at how the major swimming nations are stacking up. McIntosh, still only 19, looks every bit the dominant force she was in Paris. Australia's relay depth and sprint strength remain formidable. And the United States, across both men's and women's events, showed the breadth that has long defined its programme.