In 2005, the Polish relay team with Agnieszka Ceglarek, Marika Popowicz, Marta Jeschke and Iwona Brzezinska won the gold medal at the European Junior Championships. At the 2005 World Youth Championships, Popowicz reached the final in the 200-meter run and finished sixth. In 2007, the Polish relay team at the Junior European Championships in the line-up Martyna Ksiazek, Marika Popowicz, Agnieszka Ceglarek and Weronika Wedler and won the bronze medal behind the British and Ukrainian relay teams .
In 2009 Popowicz won the Polish championship title over 100 and over 200 meters. At the Universiade in 2009 she took second place with the Polish relay as well as a week later at the U23 European Championships in Kaunas, where she also received the bronze medal in both the 100-meter run and the 200-meter run. At the European Championships 2010 in Barcelona Popowicz was eliminated over 100 meters in the run; the Polish relay with Marika Popowicz, Daria Korczyńska , Marta Jeschke and Weronika Wedler won the bronze medal behind the relay from Ukraine and France.