"It's really a tough and close match," said spiker Zhang.
Su crossed the line in two hours, 16 minutes, 29 seconds, 14 seconds shy of his personal best set in Xuzhou two years ago. Yang from Jiangsu finished second in 2:17:36, followed by Yang Shaohui from Yunnan in 2:18:44.
The 33-year-old, who netted 21 goals last season despite needing a knee operation, was filmed at Barca's training ground in tears on Wednesday and the move could be confirmed in a matter of hours. Enditem
The top four finishers of each group will form a new group, to be based in Suzhou, to fight for the first to eighth position of the season in the second phase, which will be held between October 16-December 12.
Brazil's Santos also moved within sight of a berth in the next round with a 2-1 win over 10-man Delfin in the Ecuadorian port city of Manta.
"Lyu had a couple of chances to beat me 3-0 and again to beat me 3-1, so he'll be disappointed there because he'll feel he lost it rather than I won it, but he gave me chances and all I can do is to pick up the pieces, which I did," Selby told the tournament's website.
The result left Boca with 10 points from four matches in Group H, three points clear of second-placed Caracas FC. Independiente Medellin remained at the foot of the group with four straight defeats.
Mainz goalkeeper Robin Zentner had to be on guard to defuse Dani Olmo's effort in the 4th minute before Marcel Halstenberg headed just wide from a promising position four minutes later.
Yunnan made more errors in the second set, especially in serve and back court receiving, only to witness Beijing take the set again.
The AK senior vice president in-charge of competitions, Paul Mutwii, confirmed on Friday that the test events will involve the 200m, 400m and 800m, both men and women, and 4X400m mixed relay races to enable the organizers to try out the electronic gadgets that will be used during the next weekend's one-day event, dubbed Kip Keino Classic.
Leandro Martinez gave the hosts hope by combining with Cristian Colman and beating goalkeeper Cesar at his near post after some sloppy Flamengo defending.