|Vietnamese billiards player Tran Quyet Chien (Photo: Thanh Nien)
Former winner Tran Quyet Chien lost out to Martin Horn of Germany (world No.26) 22-40 in the first match of the qualifying round in Group G.
However, he enjoyed two consecutive victories over Choi Wan Young (world No.79) and Heo Jung Han (world No.11), both of the Republic of Korea, to win one of the two places on offer in the group to progress to the quarter finals.
Ngo Dinh Nai also enjoyed two wins over his teammate Ma Minh Cam (world No.21) and Marco Zanetti of Italy (world No.4), as well as drawing with Tasdemir Tayfun of host nation Turkey in Group E to book his place in the quarter finals.
Ma Minh Cam defeated Zanetti in the second match but lost out to Tayfun so was unable to progress to the quarter finals.
Whilst Nguyen Quoc Nguyen (world No.9) was unable to progress out of Group H.
Tran Quyet Chien is set to meet Eddy Merckx of Belgium (world No.3), while Ngo Dinh Nai will face Tayfun of host nation Turkey today in the quarter finals.