After Wasielewski had won in the quadruple sculls bronze in 2003 and silver at the 2004 U23 World Championships, he moved in 2005 in the Polish federation of four on. Together with Michał Jeliński, Adam Korol and Marek Kolbowicz he won the World Cup a third and a second place. At the World Championships in Gifu boat succeeded in winning the gold medal. 2006 won the boat at the World Cup in Munich and Poznan and defended at the World Rowing Championships in 2006 in Eton successfully the title. 2007 succeeded by the four World Cup victories in Linz and Amsterdam at the World Rowing Championships 2007 in Munich, the third title in a row. In 2008, the Polish quad was always forefront, at the World Cup was followed by victory in Munich, the second place in Lucerne and a third place in Poznan. At the Olympic Games in Beijing, the Polish foursome could ultimately well ahead of the other boats and won with more than two seconds ahead of the boats from Italy and France.
After the victory at the World Rowing Championships in 2009 and at the helm European Championships 2010, the Polish sculls could not maintain its dominance, in 2011 won the boat bronze at the European Championships and finished at the World Championships in fourth place.