Daniel Chan dealt Kelly Chen a 'dragon punch' during a duet for Mark Lui's Thank You concert last night. According to a viewer at the concert, Daniel had been trying to boost the atmosphere and accidentally threw a 'dragon punch' at Kelly. She immediately raised her head and covered her mouth, but continued the performance despite the pain. Kelly's manager later admitted that she had been 'attacked', and had received a small scrape on her lip that bled. Daniel's manager explained the two had been dancing too close to one another. Apologies for the accident and hope Kelly is fine.Among the guest performers for the evening was Kelly Chen, Daniel Chan, Alex Fong, Stephy Tang, Edmond Leung and Miriam Yeung.