Harrick's coaching career began at Morningside High School in Inglewood, California where he served as an assistant coach from 1964 to 1969 and as head coach from 1970 to 1973. He was then hired as an assistant coach at Utah State University from 1974 to 1977. Harrick then spent two seasons as an assistant coach at UCLA from 1978 to 1979. His first collegiate head coaching job was at Pepperdine University in 1979, where he led the school to four NCAA Tournament appearances and was a conference coach of the year four times.