He played collegiate soccer at Saint Louis University where he won the 1969 and 1970 Hermann Trophy as the player of the year.

In 1967, Trost's freshman year, St. Louis made it to the title game, which was ended due to weather with the score 0–0.

While Trost finished his collegiate career in 1970, he chose not to turn pro in order to be eligible for the 1972 Summer Olympics.

Trost played two of the three games at the Munich Olympics, the 0–0 tie with Morocco and the crushing 0–7 defeat at the hands of West Germany.

In 1973, Trost began his professional playing career with the St. Louis Stars of the North American Soccer League.

After leaving the NASL, Trost played a single season for the New York Arrows of Major Indoor Soccer League in 1979–1980.

In 1981, the St. Louis Steamers hired Trost to replace Pat McBride, who left the team in a contract dispute during the 1980–1981 post-season.

Trost began his coaching career with the McCluer North High School (Florissant, Missouri) boys' soccer team, while playing for the St. Louis Stars.