Gwangju - An Italian swimmer was forced to make three attempts to complete a world championship backstroke heat after a string of malfunctions with the starting equipment.
Simone Sabbioni, a national record-holder, accidentally kicked off his wedge, the angled block swimmers use to push off, and came to an abrupt halt as his fellow swimmers splashed down the pool.
Sabbioni, 22, was told he could race again - this time alone - but the device gave way for a second time, making him slip.
"It's just unbelievable this kind of thing can happen at the world championships," he told AFP.
Sabbioni - who eventually got away cleanly at the third attempt - squeezed into one of the last qualifying spots with a time of 53.85, spurred on by a roaring crowd.
"I'm happy because I got through to the semi-finals but it really wasn't easy in these kind of conditions," he said.
Sabbioni wasn't the only athlete to encounter problems at the starting line.
Minutes earlier Dylan Carter of Trinidad and Tobago also suffered issues with his block and after a protest by his coach, was granted the same opportunity for a second lonely swim.
"The first time the wedge slipped out the notch so it was a mechanical fault," he said.
"But we knew that I had the capability to be in the semi so my coach protested because it's happened to a lot of athletes."
Carter, 23, said he already had his swim suit off when he found out he'd been given a second chance to race.
"They made me swim again and I put together a better swim and made it to the semi."
But Carter said it was "unfortunate" and "not fair" that he had to swim twice to make it to the semi-finals.
"It should not be happening at any meet you know, especially if it's the world championships," he added.
Russia's Kliment Kolesnikov, who holds the world junior records in the 50m, 100m and 200m backstroke, also said he had an issue with his block, although he managed to continue with his heat and qualify in 14th place behind Sabbioni.
China's Xu Jiayu, who won silver at the 2016 Olympics in Rio, qualified in first place. The USA's Ryan Murphy - who secured gold at that Games - was also among the qualifiers in South Korea.