Fittipaldi did attempt to claim the lead in the opening stages of the 40-minute race but Binder was too strong defensively and held off the Brazilian's advances.
Not so fortunate at the start was championship runner-up Matevos Isaakyan as the SMP Racing/AVF driver failed to get away at the start in an incident that appeared to be similar to the transmission problems that hampered him in the Friday's first race.
As the grid weaved their way up to Turn 4, Isaakyan's team-mate Konstantin Tereschenko was tapped into a spin coming out of the third corner and the Russian had to retire the car.
A lap later, Alfonso Celis Jr and race one winner Henrique Chaves collided at Turn 1 as Celis appeared to brake slightly too late and caught the rear of Chaves' AVF car. The pair got restarted but Celis had to pit for a new wing.
The Fortec driver's early stop cost him dearly as he fell to ninth and was later penalised 20 seconds for making his only stop outside the pit window.
Binder and Fittipaldi had no such issues in their own stops as the pair pitted with half-an-hour to go.
Fittipaldi was the first in for fresh rear tyres and a fast out-lap gave him the opportunity pass Binder as the Austrian came out of the pits a lap later.
However, Binder was again too strong defensively and hung on to claim his fourth win of the season.
Claiming a debut podium was Tatiana Calderon who benefitted from drive-through penalties for Yu Kanamaru and Diego Menchaca after the pair were involved in an incident in the opening stages of the race as Kanamaru forced the Fortec driver onto the run-off going up to Turn 4.
Menchaca then received a penalty for passing the RP Motorsport driver under yellow flags during the same incident.
The pair finished sixth and seventh respectively, with their penalties allowing Roy Nissany and Chaves to claim fourth and fifth.
Celis and Isaakyan rounded out the field in eighth and ninth.
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