Star SAR swimmer Siobhan Haughey on Tuesday booked a place in the semi-finals of the women's 100m freestyle at the Paris Olympics.

Haughey came first in heat 4, clocking 53.02 seconds at the Paris La Defense Arena.

That's the second fastest in the heats behind Sarah Sjoestroem of Sweden.

Haughey and 15 others were through to the semi-finals which start at 3:33am Wednesday morning Hong Kong time.

She took silver in the same event in Tokyo three years ago.

Haughey has already won a bronze medal in Paris in the 200m freestyle.