French Tennis Federation (FFT) said the start was delayed due to security officials neutralising a vehicle illegally parked outside the stadium.
Start of play at the French Open between local hope Ugo Humbert and Ricardas Berankis of Lithuania was delayed on Tuesday due to a suspiciously parked vehicle outside Roland Garros, the organisers said.
A loud sound was heard outside the 5,000-seat stadium, built on the premises of the neighbouring botanical garden, and play started on Court Simonne-Mathieu about 25 minutes later than schedule.
French Tennis Federation (FFT) said the start was delayed due to security officials neutralising a vehicle illegally parked outside the stadium.
"It was a routine security intervention by the police," an FFT spokesman told Reuters. "Everything is back to normal."
A police source said the vehicle was a stolen car and security checks confirmed there were no explosives attached.
Matches on the other courts on the third day of the clay court Grand Slam started on time.
