Ustupski belonged to the ski club Wisła-Gwardia Zakopane . At the age of seventeen, he won his first national medal in third place in the team competition. Together with Janusz Guńka and Tadeusz Bafia , he became the first Polish champion in the Nordic combined in 1987. A year later in Zakopane he also won the gold medal in the individual.
His first international competition he played in January 1989 in the German Reit im Winkl where he could get his first World Cup points with a seventh place. A week later he achieved his best career result with second place in Breitenwang and the podium in the World Cup for the only time . A short time later, he won a national medal for the first time at the ski jumping championships in Wisła when he was second in the team. In the national competitions of the Nordic Combined, he was again champion in the individual and in the team. By 1994 Ustupski was able to win a total of thirteen championship titles in Nordic combined.
In his third participation in the Nordic World Ski Championships in 1991 in Val die Fiemme , Ustupski did not make it into the top 20 and came in 26th place. In 1992 he was a participant in the Winter Olympics in Albertville , where he was able to improve from eighteenth place after jumping to 8th place with good mileage. Only a few days later, Ustupski won his first and only competition in the second-rate B World Cup on February 22, 1992 in Szczyrk . At the 1994 Winter Olympics in Lillehammer , he finished 21st.