Papp began her international career as a junior with appearances at the 2000 World Junior Championships in Athletics and the 2001 IAAF World Cross Country Championships. In her first year as a senior athlete she ran for Hungary in the finals of the 3000 metres at the 2002 European Athletics Indoor Championships and the 5000 metres outdoors at the 2002 European Athletics Championships. She was the gold medallist in the 10,000 metres at the 2003 European Athletics U23 Championships the following year.