Pecz competed for Hungary in the women's 100 m breaststroke at the 2008 Summer Olympics in Beijing, Leading up to the Games, she posted a time of 1:11.15 to clear the FINA B-standard (1:11.43) by 0.28 of a second at the Hungarian Junior Championships in Eger. Swimming on the outside lane in heat three, Pecz opened up the race with a spectacular second-place feat, but faded down the stretch to hit the wall with a seventh-place time in 1:12.17. Pecz, however, failed to advance to the semifinals, as she placed forty-first out of 49 swimmers in the prelims.