ABU DHABI, July 20 (Xinhua) -- China grabbed their second straight win on Friday to secure a last eight berth at the FIVB men's under-21 world championship in Manama, Bahrain, with one match remaining in Pool A.

The Chinese U21 team won over Puerto Rico 25-23, 25-22, 25-23 after beating Morocco 25-16, 25-23, 25-13 on Thursday.

Xiu Chengcheng and Zhai Dejun teamed up again to power China's offence in Friday's game, as Xiu delivered 17 points and Zhai added 10.

Sebastian Negron came out the sole player on the Puerto Rican side who scored in double figures with 13 markers.

"Today's match was tough," said Chinese coach Liu Hao. "They did very well with their blocks and we were forced to make many mistakes. It was by no means easy to win the match and their team had a strong performance."

According to the competition formula, 16 teams were divided into four pools at the men's U21 worlds, and top two teams from each pool will qualify for the top eight classifications.

After piling six points through two games, China, who'll meet their strongest opponents of Pool A Bahrain on Saturday, have temporarily topped the group and made sure of a last eight spot, with the second-placed Bahrain on 5 points from two matches.

"We are happy to be in the second round, but we need to continue doing our best and not think about other teams," China captain Chen Leiyang said.