Firstly Allen accused Yupeng of cheating with this shot. He said it was a push, it does appear to be so. A push is defined as the cue, the white and the contact ball all being in contact at the same time. Allen doesn't seem to object at the time though.
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The end of the match is amazing. Allen seemingly finishes up to leave himself two frames away from levelling when this happens.
http://www.youtube.com/watch?v=rJoGD3D4ZI8
