DePalmer graduated from the University of Tennessee , where his father worked as a tennis head coach. Right at the beginning of his career he had his greatest success as a single player on the ATP World Tour , when he was in the final at the tournament in Ancona , in which he was defeated by Anders Järryd . He also reached the semifinals of the tournament in Vienna and the semifinals of Tampa the following year . In 1984 he was in his first double final in San Francisco . He won his first double title in Vienna in 1985, and a second title followed in the same year. 1986 was his most successful year with three tournament victories.
In the course of his career, he won six double titles, six more times he was in a final. He reached his highest ranking in the tennis world rankings in 1983 with position 35 in singles and 1986 with position 20 in doubles.
His best individual result in a Grand Slam tournament was reaching the third round, which he achieved in all four tournaments. In the doubles competition he reached the semi-finals of the US Open in 1985 on the side of Gary Donnelly , at the Australian Open , in Wimbledon and at the French Open , he reached the second round in the same year.
After his professional career, which he had ended due to persistent back problems, DePalmer worked as a trainer for Boris Becker from August 1995, among other things . The married DePalmer, who has a son from his first marriage, previously worked for Nick Bollettieri , for whom both his father and brother had already worked. He died in Knoxville in August 2021 of cancer.