Leo delighted the home crowd as he overcame the three-time world champion 6-11, 11-7, 11-7, 10-12, 11-4 in a gruelling five-game battle at the Hong Kong Squash Centre.

Egypt's Ali Farag, the world number four, awaits for the outsider from Hong Kong in the next round after he beat England's Tom Richards 11-2, 7-11, 12-10, 11-7.

"I feel amazing because I didn’t expect much before the match,” said Au.

"I thought that he would be more focused in the fifth game and there would be more pressure on me. 

"It was a mistake to lose that match point, but I’m happy to win in front of my home crowd because this is my first time getting to the second round."

Reigning world champion Karim Abdel Gawad of Egypt did not suffer the same fate as his compatriot as he reached the second round with an 11-7, 11-9, 9-11, 11-5 victory over Cesar Salazar of Mexico.

Gawad will take on Australia's Cameron Pilley, who ousted Germany's Raphael Kandra 11-8, 11-6, 11-4.

In the women's draw, Malaysian Nicol David began her bid for an 11th Hong Kong Open crown with a four-game win over Canadian qualifier Danielle Letourneau.

David was not at her best but was still able to progress courtesy of an 11-2, 11-6, 9-11, 11-3 victory.

The Malaysian star will play Annie Au of Hong Kong in the next round after she beat compatriot Tong Tsz-Wing 13-11, 11-9, 11-3.

The tournament in Hong Kong is due to continue tomorrow.