Kinnear studied between 1984 and 1988 at Clemson University and was elected to the best selection of All-American in 1987. He was a professional tennis player in 1988 and first played on satellite tournaments, where he gained his first world ranking points. The following year he won in São Paulo on the side of David Wheaton his first doubles title on the ATP Challenger Tour. His first doubles title on the ATP World Tour, he won in 1991, the same year he succeeded the individual title at the Challenger tournament in Puebla by a final win against Luis Herrera. In 1992, one of its most successful years, he won the individual title at the Challenger tournament in Perth and stood in the doubles final of the tournaments of Vienna, Scottsdale and the ATP Masters Series Miami and Indian Wells. Overall, he won four doubles titles during his career, he also stood 15 times in a final. Its highest listing in the tennis world ranking he reached in 1992 with position 163 in singles and position 24 in doubles.
His best individual result at a Grand Slam tournament was reaching the second round of Wimbledon 1992. In the doubles competition, he came at the Australian Open and Wimbledon to the second round before.
After the end of his professional career, he has worked as a coach at the University of Illinois. He is married and has one daughter.