<Tr> <Th_colspan="2"> Current champion </Th> </Tr> <Tr> <Td_colspan="2"> Kenny Perry </Td> </Tr> <P> The U.S. Senior Open is one of the five major championships in senior golf, introduced 37 years ago in 1980 . It is administered by the United States Golf Association (USGA) and is recognized as a major championship by both the PGA Tour Champions and the European Senior Tour . The lower age limit was 55 in 1980, but it was lowered to 50 for the second edition in 1981, which is the standard limit for men's senior professional golf tournaments . By definition, the event is open to amateurs, but has been dominated by professionals; through 2016, all editions have been won by pros . Like other USGA championships, it has been played on many courses throughout the United States . </P> <P> Allen Doyle became the oldest U.S. Senior Open Champion in 2006, winning two weeks before his 58th birthday . </P>

How old do you need to be to play in the senior open