They joined China League Two , third tier of Chinese football league system in the 2012 league season .
Roc also refers to Shenzhen as nickname of the city ( PengCheng , city of roc ) .
Roc joined China League Two , third tier of Chinese football league system in the 2012 league season .
Roc also refers to Shenzhen as nickname of the city ( PengCheng , city of roc ) .