Ducati man Bautista recovered from fourth place on the grid in Saturday's opener to score his seventh win of the season and give himself a 29-point cushion over Jonathan Rea, who finished fourth but very nearly denied Redding his first podium finish in a full-distance race aboard a BMW.
It was only at half-distance in the 22-lap that Bautista moved to the fore, having spent the opening laps in third place behind early leader Razgatlioglu and poleman Rea.
Last year's title protagonists swapped the lead multiple times after Rea first took back the lead on lap 6 at the Turn 15-16-17 complex, and it was a similar move four laps later that allowed Bautista to close in and pass Razgatioglu for second.
Then on the following lap, Bautista was able to use the power of his Ducati V4 R Panigale to breeze ahead of Rea at the start of lap 11, as spots of rain began to fall around several parts of the circuit.
The rain never intensified enough to significantly wet the track, but it did appear to allow the BMW of a charging Redding to make it a four-way battle for the lead in the second half of the race.
On lap 14, Redding demoted Razgatlioglu at the penultimate corner to move up into third, and two laps later he was able to ease ahead of Redding at Turn 1 to grab second behind Bautista.
At one point it looked as if Redding had the pace to challenge for a first BMW victory, but as the race moved into its closing stages Bautista was able to eke out a one-second advantage, which was out to 2.1s by the time of the chequered flag.
Instead Redding was forced to defend second against Razgatlioglu, who had re-passed Rea for third at the start of lap 20.
Although too far back to challenge at his preferred passing spot of Turn 1 on the final lap, Razgatlioglu was able to close up to Redding through the first half of the lap and muscle his rival aside at the fast Turn 13 right-hander at the back of the circuit.
Redding was forced out on to the green tarmac runoff and found himself with Rea drawing alongside into the following right-hander of Turn 15, but Redding responded with an aggressive move into the Turn 16 left-hander to regain the initative, and hung it around the outside of Turn 17 to keep the place.
Behind the leading quartet, Axel Bassani was best of the rest on the Motocorsa Ducati, followed by Andrea Locatelli on the second Yamaha.
Michael Ruben Rinaldi's race never recovered from a poor start from third on the grid as the works Ducati man trailed home seventh.
Iker Lecuona recovered from 12th on the grid to finish eighth for Honda ahead of Alex Lowes on the second Kawasaki, while Garrett Gerloff was the final top 10 finisher on his GRT Yamaha.
Redding's temporary BMW teammate Peter Hickman was a lapped 22nd, one place ahead of debutant Ryan Vickers on the Pedercini Kawasaki.
Most World Superbike - Race 1 results:
| Cla | # | Rider | Bike | Laps | Time |
|---|---|---|---|---|---|
| 1 | 19 |  Alvaro Bautista | Ducati | 22 | 34'00.965 |
| 2 | 1 |  Toprak Razgatlioglu | Yamaha | 22 | 2.109 |
| 3 | 45 |  Scott Redding | BMW | 22 | 2.603 |
| 4 | 65 | Jonathan Rea | Kawasaki | 22 | 2.718 |
| 5 | 47 |  Axel Bassani | Ducati | 22 | 7.951 |
| 6 | 55 | Andrea Locatelli | Yamaha | 22 | 9.105 |
| 7 | 21 | Michael Ruben Rinaldi | Ducati | 22 | 12.181 |
| 8 | 7 | Iker Lecuona | Honda | 22 | 12.435 |
| 9 | 22 | Alex Lowes | Kawasaki | 22 | 13.028 |
| 10 | 31 |  Garrett Gerloff | Yamaha | 22 | 13.119 |
| 11 | 76 |  Loris Baz | BMW | 22 | 17.379 |
| 12 | 44 | Lucas Mahias | Kawasaki | 22 | 26.631 |
| 13 | 5 |  Philipp Oettli | Ducati | 22 | 27.364 |
| 14 | 29 |  Luca Bernardi | Ducati | 22 | 31.278 |
| 15 | 97 | Xavi Vierge | Honda | 22 | 37.260 |
| 16 | 52 |  Oliver Konig | Kawasaki | 22 | 50.854 |
| 17 | 36 |  Leandro Mercado | Honda | 22 | 51.431 |
| 18 | 3 |  Kohta Nozane | Yamaha | 22 | 53.058 |
| 19 | 50 |  Eugene Laverty | BMW | 22 | 58.942 |
| 20 | 23 | Christophe Ponsson | Yamaha | 22 | 1'03.366 |
| 21 | 2 | Roberto Tamburini | Yamaha | 22 | 1'03.407 |
| 22 | 10 | Peter Hickman | BMW | 22 | 1'05.450 |
| 23 | 77 | Ryan James | Kawasaki | 22 | 1'06.797 |
| 35 |  Hafizh Syahrin | Honda | 20 | 2 Laps | |
| 6 | Michal Prasek | BMW | 16 | 6 Laps | |
| View full results | |||||
