Ponomaryova represented the Unified team at the 1992 Barcelona Olympics. In the semi-finals she ran 53.98 sec, to qualify for the final as the third fastest. However, in the final she only managed 54.83 to finish sixth. At the following years World Championships in Stuttgart, she reached her peak running 53.48 sec to win the bronze medal. This was her first (and only) individual medal at Olympic or World Championship level. The race was won by Sally Gunnell in a then world record of 52.74. Ponomaryova also won a silver medal in the 4x400 metres relay.