At the 2008 Summer Olympics in Beijing, Postica qualified for the men's 100 m breaststroke by eclipsing a FINA B-standard entry time of 1:03.71 from the Russian Open Championships in Saint Petersburg. He challenged five other swimmers on the second heat, including two-time Olympian Nguyen Huu Viet of Vietnam. Postica raced to second place by 0.11 of a second behind Panama's Edgar Crespo in 1:03.83. Postica failed to advance into the semifinals, as he placed fifty-fourth overall on the first night of preliminaries.