Rea started the 10-lap encounter from pole position but could do little to prevent the Yamaha of Razgatlioglu to take the lead into Turn 1, as Rinaldi held third position from teammate Scott Redding.
The Italian dispatched Rea’s Kawasaki with ease on lap 2 and then set about chasing Razgatlioglu for the lead, breaking the circuit lap record to close the gap to the Turkish rider.
On lap 6, Rinaldi dived down the inside of Razgatlioglu under braking into Turn 11 in what turned out to be the decisive move of the race.
From there on there was no stopping the 25-year-old, who cruised to his third career win in WSBK following triumphs in Estoril last year and the opening Misano race on Saturday.
Rea played no role in the victory fight, finishing nearly two seconds behind Rinaldi in third, with Redding also having an uneventful race en route to fourth.
Alex Lowes finished fifth again on the second factory Kawasaki, meaning the top five order was an exact replica of the first race of the weekend.
Alex Bassani was the lead independent rider in sixth on the Motocorsa Ducati, beating the works BMW of 2013 champion Tom Sykes, as GRT Yamaha’s Garrett Gerloff completed an incredible charge from the back of the pack to claim eighth.
The top 10 was completed by Yamaha’s Andrea Locatelli and the lead works Honda of Alvaro Bautista.
GoEleven Ducati rider Chaz Davies crashed at Turn 2 on the opening lap of the race, his second consecutive DNF of the weekend, joining Michael van der Mark (BMW) and Lucas Mahias (Puccetti Kawasaki) in the list of retirees.