When Regan O'Rourke tees off at the Pinehurst (N.C.) Country Club No. 2 course today at 1 p.m., it will be only the third time that an American University team has competed in a Division I NCAA golf championship.

O'Rourke, AU's No. 1 golfer, is one of four Washington-area players who led the Eagles to a 22-2 team record this this season, an East Coast Conference championship and runner-up position in the the Eastern Intercollegiate Championships.

For the last few years, the golf program at AU was primarily a participatory sport. But a strange set of circumstances has enabled American to become one of the 30 teams to compete for the national title over the next four days.

Senior Greg Carpousis, from St. John's High, went to the University of Miami but grew disillusioned with the city in 1979 and transferred to American, where his girlfriend was attending school.

Wade Heintzelman, a senior from Walt Whitman High, didn't like his engineering classes at the University of Maryland. Heintzelman heard his friend Carpousis had transferred to AU and did likewise the same year.

Ian Noel, a junior from Bethesda-Chevy Chase High, never had grown comfortable at Louisiana State in 1981. When he heard Carpousis and Heintzelman were eligible and playing well, he transferred to American.

O'Rourke, a junior, made a brief stop at Montgomery Community College before deciding he didn't want to miss out on something that just might be big. "Regan knew with the other three, they could do something like we're doing now," said Coach Ray Murphy, who welcomed them all without hesitation.

The fifth player is junior Scott Jefferey, who grew up in Colombia, South America, and is the son of a career Army officer.

The biggest victory to date for the Eagles is a one-stroke triumph over perennially strong Temple to win the ECC championship.

But the competition will be even tougher at Pinehurst. UCLA is the favorite, followed by defending champion Brigham Young and Atlantic Coast Conference teams Clemson, North Carolina, North Carolina State and Wake Forest.