Dzingai represented Zimbabwe at the 2008 Summer Olympics in Beijing where he was selected as the flag-bearer for the Zimbabwean contingent. He competed in the 200 metres and placed first in his first round heat, just in front of Christian Malcolm with a time of 20.25 seconds. He improved his time in the second round to 20.23 seconds and won his race again, this time in front of American sprinter, Walter Dix. He ran his semi final race in 20.17 seconds and placed second after Churandy Martina, but again before Dix. With his appearance in the Olympic 200 meter final, Dzingai became the most accomplished sprinter in Zimbabwean history. In that race, Usain Bolt shattered the world record, and Dzingai ran a time of 20.22, which placed him unofficially in sixth place. However, due to the disqualifications of Martina (second) and Wallace Spearmon (third) he moved up to the fourth place overall, behind Dix and missing out on the bronze medal by 0.24 seconds.