His first international jumping was for the World Cup on January 27, 1996 in Zakopane . On the large hill he reached the 43rd place. On February 10, 1996, he jumped to 45th place in ski flying on the Kulm . At the ski flying world championship taking place one day later in 1996 , he came in 46th place. At the Nordic World Ski Championships in Trondheim in 1997 , he again only reached 46th place in the competition on the large hill. In the same year he was able to win the normal hill title at the Winter Universiade in Muju, South Korea . At the 1998 Winter Olympics in the Japanese Nagano but he did not get beyond the 45th place on the large hill. On January 17, 1999, Kruczek was able to achieve World Cup points for the first time with 25th place in Zakopane. At the Nordic World Ski Championships in 1999 in Ramsau am Dachstein , he was able to increase his performance to 1997. He jumped 32nd on the large hill and 41st on the normal hill. At the Winter Universiade held in Poprad , Slovakia that same year , he was able to defend his title on the normal hill and achieved sixth place on the large hill. There followed two seasons with changing performances. Most of the time he fell short of expectations and ended up outside of the points. In February 2001, however, he won the gold medal at the Winter Universiade in Zakopane, both on the normal hill and, for the first time, on the large hill. On December 9, 2001 he was able to jump on the podium with the team in the Villach team competition for the first time and came in 3rd place together with Robert Mateja , Adam Małysz and Wojciech Skupień . After his performance remained below expectations, he was removed from the senior national team and added to the Continental Cup team at the start of the 2002/03 season . But he was also unsuccessful in the Continental Cup and ended his active jumping career after the last competition of the season on February 23, 2003 in Lauscha . Previously, he had achieved third place for Poland in the team competition at the Winter Universiade in Tarvisio, Italy, together with Grzegorz Śliwka and Krystian Długopolski .
After he had given up active jumping, he completed his training as a ski jumping coach and was then coach of the Polish B national team under Heinz Kuttin . From 2008 he was coach of the national team after his predecessor Hannu Lepistö was dismissed on March 14, 2008. In February 2016, Kruczek announced his resignation from the post of head coach of the Polish national team at the end of the 2015/16 season. From the 2016/17 season until the end of March 2019, Kruczek coached the Italian national ski jumping team. After three years in Italy, he returned to Poland and took over the position of head coach of the women's squad. In addition, Kruczek became technical delegate and ski jumping judge of the FIS at the beginning of January 2020 .