American Justin Ress won gold in the 50m backstroke in dramatic circumstances at the World Championships in Budapest on Saturday after officials overturned his initial disqualification following a lengthy review.

Victory was earlier awarded to compatriot Hunter Armstrong after it was ruled that no part of Ress’s body was above the water as he reached first for the wall.

Ress, who had set the pace in the heats and the semi-finals, was later reinstated as the winner and the medal ceremony held again, with Armstrong taking silver and Polish teenager Ksawery Masiuk having to settle for bronze.

Canadian Summer McIntosh continued her superb run in the Hungarian capital after the 15-year-old beat fellow teen Katie Grimes of the US to collect the 400m medley title. US swimmer Emma Weyant came third.

“It’s really cool to race someone like Katie as she is around my age and she’s a really tough competitor,” said McIntosh.

Gregorio Paltrinieri, gold medallist at the Rio Olympics, set a new championship record in the 1,500m freestyle, comfortably finishing ahead of Robert Finke and Florian Wellbrock in a time of 14:32.80.

Jacobs preparation on track

Olympic sprint champion Lamont Marcell Jacobs ramped up his preparations for next month’s World Championships in Eugene, Oregon, by winning his fifth Italian national men’s 100m title on his comeback from a muscle injury.

Jacobs picked up the injury in his 100 metres win at a meet in Savona last month and was forced to withdraw from Diamond League meetings in Eugene, Rome and Oslo.

“The goal of this day was to run twice, in the heats and final, just as we did, to regain the rhythm after (a) small injury,” Jacobs, who claimed victory in 10.12 seconds, said after his win on Saturday.

“Eugene is a great track with lots of wind in (your) favour all the time. I’m looking forward to competing at the worlds and testing it out.”

Jacobs became the first Italian to win Olympic 100 metres gold in Tokyo.