The blast struck in Banu district in the North West Frontier Province, which is plagued by attacks and bombings by Taliban rebels.
"The blast took place during a volleyball match and according to initial reports it appears to be a suicide attack," district police chief Mohammad Ayub Khan told AFP.
"Three people were killed and 11 others were injured."
Police spokesman Shahid Hameed confirmed it was a suicide attack, while another police official said early reports suggested a man drove a car packed with explosives onto the field as people gathered to watch the match.