"She was on the list a few days a ago. We do not know what happened at the last moment," her father told Sina.com. "Do not bother her right now. She needs to take a break by herself."
Reports link Yang's dismissal to a drug scandal during the 2001 National Games in which Yang tested positive and was banned by the national team.
Another weightlifter Tang Gonghong, a gold medalist in the Athens +75kg category, will also miss the Beijing Games due to her slumping form.
Injuries played a big role in naming China's badminton team. China has three tickets for the women's badminton singles competition, and with world No 1 and 2 Xie Xingfang and Lu Lan automatically through the battle for the remaining spot was a showdown between Zhang Ning and Zhu Lin.
Zhu appeared on the brink of taking the spot after winning the 2007 World Championships as Zhang struggled with a knee injury.
With a much better record in major international competitions over the past year, 24-year-old Zhu seemed to be a shoo-in for her first Olympic berth, until the last moment when Zhang recovered from the injury and got the nod.
Zhu was devastated, but her mother offered some comforting words for Zhu, who will have to wait another four years for Olympic glory.
"Zhang Ning is 33 and still competes for China in the Olympics," Zhu's mother told Sina.com. "Zhu still has a good future and has the chance to compete in the Olympics later."
Injury woes
Other stars were forced to withdraw from Games consideration with injuries as well.
Olympic champion Xing Huina will not be able to defend her women's 10,000m title on home soil.
The 24-year-old Shandong native beat Ethiopians Ejegayehu Dibaba and Derartu Tulu to win in Athens.
But she missed the World Championships in Osaka with a knee injury and moved to the US in January to train with well-known China-born coach James Li. But it did not seem to help.
She also lost her former coach Wang Dexian, who was banned for life after Sun Yingjie, another athlete under his wing, failed a drug test in 2005.
In wrestling, Wang Xu, who won China's first wrestling Olympic gold four years ago, would have been a favorite on the mat. In the past four years, she established herself as one of the world's best wrestlers in big tournaments and has a better record than her teammates in Olympic qualifiers.
But she hurt her shoulder in a training session earlier this month, forcing her to say a premature goodbye to the Beijing Games.
But Wang said she will devote her life to the sport.
"It's not the end of the world. I will come back after four years. I never give up," she told Sina.com.
Other high-profile names joining the injury list are Olympic pommel horse champion Teng Haibin, China's only gymnastics gold medalist in Athens, women's 100m breaststroke winner Luo Xuejuan, who has retired from the sport due to a heart problem, and women's soccer player Qu Feifei, who suffered a fibula fracture in a warm-up last week.
The nonstop circus that is China's men's soccer team is also not free of roster surprises; this time the victim is striker Zhu Ting.
Zhu has been a usual starter in the past and his Olympic chances seemed never in doubt.
But the sudden reshuffling of the coaching staff three weeks before the Games, which saw Serbian head coach Ratomir Dujkovic replaced by Chinese Yin Tiesheng, changed Zhu's fate.
Dujkovic was a big fan of Zhu, but Yin was not as impressed and dropped the striker in a bid to erase the influence left by the coach's predecessor.