Murphy had led the event for the first three days of competition after four bullets but the Belgian chipped away reducing the gap and finally overthrew her today.
On being overtaken the Irish girl said, "It's difficult to keep ahead but I'm trying my best. Everyone is really good. All the girls have so much experience, so really I'm just trying my best. I've given it everything over the last three years and I'm pleased it has come together."
The Radials resume at 12:10 local time on the Weymouth Bay West Course.
1. Evi Van Acker (BEL) - 23pts
2. Annalise Murphy (IRL) - 24pts
3. Marit Bouwmeester (NED) - 26pts
4. Lijia Xu (CHN) - 30pts
5. Alison Young (GBR) - 37pts
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