Madeline Perry battled back from two games down to beat England's Sarah-Jane Perry and book a place in the quarter-finals of the World Championship.
The seventh seeded Northern Irishwoman, who at 37 is the oldest player in the tournament, earned a 7-11 10-12 11-9 11-9 11-6 victory in Malaysia.
Perry's win sets up a last-eight meeting with Egyptian third seed Raneem El Weleily on Friday.
The Ulsterwoman beat El Weleily in New York in January.
That victory ended a losing sequence against the Egyptian which included last year's British Open quarter-final.
"A tough 3-2 win and a comeback from me today against a very skilful opponent," said Perry on Twitter after her victory on Thursday.
"Delighted to be into the quarter-finals of the World Championships."
El Weleily continued her run in Penang with a 11-7 11-7 11-1 win over 10th seed Dipika Pallikal of India.