Atasoy qualified for the men's 100 m breaststroke at the 2008 Summer Olympics in Beijing, by clearing a FINA B-standard time of 1:02.43 from the Croatian Open Championships in Dubrovnik. He challenged seven other swimmers on the fourth heat, including three-time Olympian Jakob Jóhann Sveinsson of Iceland. Atasoy edged out Serbia's Čaba Silađi to take the second spot by six hundredths of a second (0.06), posting his lifetime best of 1:02.25. Atasoy failed to advance into the semifinals, as he placed thirty-ninth overall on the first night of preliminaries.