Australia’s Kyle Chalmers remains bullish of breaking a personal barrier after bagging a 100m freestyle bronze medal at the world titles.

Chalmers and fellow Australian Liz Dekkers (women’s 200m butterfly) both secured bronze on Thursday night in Singapore.

Chalmers collects a 14th career medal at world titles, finishing behind Romania’s sizzling David Popovici (46.51 seconds) and American Jack Alexy (46.92).

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Chalmers clocked 47.17 — he is yet to swim the race in less than 47 seconds, which is now the realm of world winners.

“I have been training hard for that moment, I desperately wanted to get a 46 out tonight, but it wasn’t quite there,” he told Channel Nine.

“But to get on the podium is so special.”

The bronze medal maintained his perfect record of finishing in the top three in his six appearances in Olympic or world championship 100m freestyle finals.

Chalmers has twice logged personal best times of 47.08 and, at the age of 27, believes he can improve — but he now has other priorities.

Chalmers and his partner, Norwegian swimmer Ingeborg Loyning, are expecting their first child next month.

“I’m just really excited to go home now and become a dad, that is my biggest priority this year — that (swim) was just a bit of fun,” he said.

Chalmers also won gold in Singapore when anchoring Australia’s 4x100m freestyle relay team on Sunday’s opening night.

Earlier Thursday night, Chalmers’ compatriot Dekkers took the bronze in a women’s 200m butterfly won by Canadian star Summer McIntosh — the 18-year-old’s third gold of the titles.

“Physically, I’m not at my best,” Dekkers said.

“So I knew that mentally, I had to be there ... I love racing, and that’s why we all do this, because there’s something about standing behind the blocks that we all love.”

Decorated Dolphin Mollie O’Callaghan cruised through her women’s 100m freestyle semi-final, advancing to Friday night’s medal race as fastest qualifier.

O’Callaghan, already with golds in the 200m freestyle and women’s 4x100m relay in Singapore, won her semi in 52.82 seconds but fellow Australian Olivia Wunsch withdrew due to illness.

O’Callaghan later Thursday night will race in the women’s 4x200m freestyle relay and, if victorious, will equal Ian Thorpe’s Australian record for most golds at world titles, 11.