Mosquera represented Colombia at the 2008 Summer Olympics in Beijing, where he competed for the men's 400 metres. He ran in the fifth heat against seven other athletes, including Belgium's Jonathan Borlée and United States' LaShawn Merritt, both of whom were heavy favorites in this event. He finished the race in seventh place by forty-four hundredths of a second (0.44) behind Grenada's Alleyne Francique, with a time of 46.59 seconds. Mosquera, however, failed to advance into the semi-finals, as he placed forty-fifth overall, and was ranked farther below three mandatory slots for the next round.