Just behind, Tarjei Bö came in fifth in the close race.
Between the third and 15th man was 17 seconds apart.
Martin Ponsiluoma, who finished second, shot away with four booms and finished eleven.
In the last shot, Quentin Fillon Maillet and yesterday's winner Johannes Kühn came in at the same time.
The Frenchman shot full while Kühn after three spotless shooters got three booms and only finished in 15th place - a big loss.
Behind came a large group to settle for second place.
Sebastian Samuelsson shot a boom but still had a hang in third place when he went out as eight - barely three seconds from third place.
The Swede, Desthieux and Bö got a gap and made up for third place after winning Fillon Maillet and the French compatriot Emelien Jacquelin who came second.