Marques was in 1986 in the second round of the junior tournament, the French Open, and in the quarter-finals of the junior tournaments at Wimbledon and the U.S. Open. The following year, he was in at the French Open, both in single as well as double the quarter-finals of the junior competition. As a tennis player, he celebrated his success mainly on the ATP Challenger Tour, where he was able to win five individual titles and 19 doubles titles during his career. After he was defeated in 1995 in Newport and 1996 in Bournemouth each in the doubles final, he won in 1997 on the side of his compatriot João Cunha e Silva in Casablanca his first and only doubles title on the ATP World Tour against the two local heroes Karim Alami and Hicham Arazi. Its highest listing in the tennis world ranking he reached in 1995 with position 86 in the singles and in 1997 with position 58 in doubles.
His best individual results in Grand Slam tournaments were to reach the second round of the Australian Open, the French Open and the U.S. Open. In the doubles competition, he reached in 2000 on the side of Tom Vanhoudt the quarterfinals of the Australian Open.
Marques played 1986-2002 39 single and 19 double appearances for the Portuguese Davis Cup team. His greatest success with the team was participating in the first round of the World Group in 1994. During the defeat to Croatia, he lost both his singles matches against Igor Sarić and Goran Ivanisevic and the double. In the Summer Olympics 2000, he stepped up to the double of Portugal. However, on the side of Bernardo Mota, he retired in the first round against the double of the Bahamas.