today cleaning crews in pittsburgh are still recovering after an estimated 50,000 kenny chesney fans attended his concert at hynes field saturday and left this behind. >> the kenny chesney is the most difficult crowd for our employees to work with of any events of the year. >> it seems the 45-year-old country star may have underestimated his fans' energy levels when he spoke to cnn last year. >> it's going to be a fun, very energetic, probably loud night of music. >> most of his shows are day-long events where tailgating is encouraged. unfortunately this parking lot brawl was just one of at least ten large fights that broke out at the stadium saturday. with more than 70 people either arrested or cited for their behavior. >> we had a hard time getting police. a lot of police didn't want to