Chad Le Clos retained his world 200m butterfly short-course crown in Canada on Tuesday night‚ but Cameron van der Burgh suffered a shock exit in the men’s 100m breaststroke.

Le Clos‚ who won four titles at the previous edition of this gala in 2014‚ was third going into the final 50m‚ but he powered into the lead over the last two laps to push American Tom Shields into second place by nearly a second.

The 2012 Olympic champion‚ a disappointing fourth in this event at the Rio Games in August‚ clocked his best time of the year‚ 1min 48.76sec‚ which was two-tenths of a second short of the world short-course record he set three years ago.

Of the three swimmers who beat Le Clos at the Olympics‚ the only one in action in Canada was Hungary’s silver medallist Tamas Kenderesi.

But Kenderesi failed to qualify for the eight-lane final by one spot‚ managing only the ninth-best time overall — Van der Burgh suffered the same fate.

Van der Burgh‚ the silver medallist in this race at the Rio Games‚ missed out on Wednesday's final by just two-hundredths of a second.

His 57.67 effort in the semifinals was more than a second off his season’s best.

It was a shock on paper‚ although Van der Burgh had admitted in the build-up that his preparation had been far from ideal‚ having been sidetracked by his pending move from Pretoria to Cape Town.

His friend and training partner Giulio Zorzi was eliminated in the heats‚ although he had the consolation of being one of the quickest over the first 50m‚ which should give him some confidence going into the 50m breaststroke on Friday.

Myles Brown‚ another Olympian in the South African team‚ was 10th fastest in the men’s 400m freestyle heats‚ which meant he failed to qualify for the final.

Also not progressing beyond the heats were Ricky Ellis and Jarryd Baxter (both men’s 100m backstroke)‚ Neil Fair (200m individual medley)‚ Eben Vorster (200m butterfly and 200m individual medley)‚ Kaylene Corbett (women’s 50m breaststroke) and Mariella Venter and Gabi Grobler (both women’s 100m backstroke).

The SA men’s team of Doug Erasmus‚ Alaric Basson‚ Alard Basson and Eben Vorster were 13th overall in the 4x100m freestyle relay.

In Wednesday’s action‚ Le Clos begins the defence of his 100m butterfly and 200m freestyle world titles.

The SuperSport broadcast of the heats begins at 4pm SA time with the finals set for 1am Thursday morning. - TMG Digital