Sports officials suspended the double Olympic champion from competition, national team training and commercial activities last November after he was given seven days’ detention for driving a Porsche without a license.
He won the 200m freestyle title on his comeback at the Chinese National Swimming Championships on Monday, clocking an impressive 1:46.04.
Sun became a huge star in China after winning the 400m and 1500m freestyle golds at London 2012, and took three titles at the world championships last year.
|Chinese swimming star Sun Yang. ( MCT)|
But the 22-year-old sparked controversy when he was found not to have a license after a white Porsche Cayenne he was driving was rear-ended by a bus in Hangzhou, his hometown in eastern China.
Sports authorities said “he violated the basic principles of morality and went against the spirit of sport,” state media previously reported.
His latest victory was met with mixed feelings from Chinese sports fans.
“This is someone without morals,” one netizen posted Tuesday on Sina Weibo, a Chinese equivalent of Twitter. “It is not his nature that is bad, but he just has the heart of a child,” another user responded.
“Congratulations on your return,” said one more positive poster.
Sun was previously embroiled in controversy after his long-time coach Zhu Zhigen told him to end his relationship with a flight attendant.
The two fell out over the issue, and Sun was accused of lacking respect for his mentor.
Amid the row, The Zhejiang College of Sports issued a stern statement accusing Sun of “breaking a series of team rules,” which domestic media said included breaking night-time curfews and refusing to train.