SYDNEY, March 17 — World record-holder Mollie O’Callaghan upstaged Olympic champion Ariarne Titmus to win the 200m freestyle in the fastest time this year at Australia’s NSW State Championships today.

The 19-year-old hit the wall in 1min 54.76secs, which would have earned her gold at the world championships in February, an event she skipped to focus on this summer’s Paris Olympics.