Gotz represented the Czech Republic at the 2008 Summer Olympics in Beijing, where he competed for the men's 400 metres. He ran in the fourth heat against seven other athletes, including Great Britain's Martyn Rooney and Jamaica's Ricardo Chambers, both of whom were heavy favorites in this event. He finished the race in sixth place by one hundredth of a second (0.01) ahead of Japan's Yuzo Kanemaru, with a time of 46.38 seconds. Gotz, however, failed to advance into the semi-finals, as he placed forty-second overall, and was ranked farther below three mandatory slots for the next round.