SMP Racing/AVF driver Orudzhev was on the offensive from the start as he went round the outside of Fittipaldi at Turn 1 to claim second place and put pressure on polesitter Alex Palou.
The Teo Martin Motorsport driver kept his lead during the opening stages of the 40-minute race with Orudzhev happy to wait for an opportunity to pass Palou rather than pushing his tyres too hard.
Fittipaldi, who came into the second race with an 18-point lead in the championship, tried to challenge Orudzhev in the early running but he locked his brakes going into Turn 1, ran through the gravel and hit the barrier.
At the front of the field, Palou pitted with 27 minutes still remaining but Orudzhev waited until the halfway mark to make his own mandatory stop and his quicker in-lap allowed him to come out 0.1 seconds ahead.
Palou did try to pressure Orudzhev into making a mistake but he absorbed the pressure and started to build a gap that extended to 5.4s by the chequered flag.
Behind the lead pair Diego Menchaca claimed his first podium of the season, his Fortec car having had an engine change overnight after being down on power in race one.
Menchaca was behind championship contender Matevos Isaakyan going into the final 10 minutes, but a great outbraking move at the end of the back-straight gave him third place.
The race got worse for Isaakyan, who was looking to take advantage of Fittipaldi's retirement to close the gap in the championship, as he outbraked himself at the end of the long back straight on the penultimate lap and allowed Roy Nissany to move up to fourth.
Isaakyan then tangled with Konstantin Tereschenko and fell to sixth, with Alfonso Celis Jr moving up to fifth.
Tereschenko, who damaged his car in the incident, fell to seventh ahead of Yu Kanamaru.
Race one winner Rene Binder finishing a lap down in 10th, behind Giuseppe Cipriani, after his car's engine stalled as the grid set off on the formation lap.
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