Ducati rider Bautista beat Razgatlioglu to victory in what turned out to be the only race of the weekend in Portugal to run to its full 20-lap distance, as the opening race on Saturday was delayed and shortened to 14 laps owing to a major accident in a World Supersport 300 support race.
When the opening race did finally get underway, the shorter distance played into the hands of Yamaha's reigning champion Razgatlioglu, who passed Jonathan Rea for the win as Bautista recovered from ninth on the grid to second.
Another win in the Superpole race allowed Razgatlioglu to claw back more valuable ground in the title chase, but after Bautista's victory on Sunday the gap between the pair stands at 56 points with three rounds to go.
Reflecting on the final European weekend of the season before WSBK heads to three flyaways to complete the season, Bautista admitted preserving his tyres over the course of the 20-lap final race was key to winning.
“[In the first race on Saturday] I needed the last six laps of the race to get to Toprak and fight for victory,” said Bautista.
“In the Superpole Race, I knew it was maybe difficult to beat Jonathan and Toprak because they were very fast. I think they were a bit better than us at this track with these conditions.
"I was very determined, and my plan was to stay with them because I can finish with them, that would mean I have the chance in [Race 2] to fight for the victory.
“In [Race 2], I had a better position on the grid. I made a normal start and I lost position to Jonathan, but I was there. When Jonathan was in front, Toprak was behind him just saving the tyre life.
“I think Jonathan was struggling a little bit more than Toprak to push. I decided to take the lead and increase the pace, make the others force their tyre.
“I’m happy because in the last laps, even if Toprak tried to overtake me a couple of times, he was struggling more so in the last few laps he stayed away.”
Razgatlioglu went into the final race aiming for his second treble win of the season after he had achieved the feat earlier this season at Donington Park, but came up 2.2 seconds short as his pace dropped off considerably in the closing laps after he lost the lead to Bautista.
“In the Superpole Race, everybody was pushing the limit because it was 10 laps,” said Razgatlioglu. “You don’t need to keep the rear tyre.
“I was also pushing on the limit, especially in the first corner. Because I knew, when Alvaro passed me, I needed to pass him because on all the straights, his bike was very fast, and this track isn’t easy to pass on.
“My strategy worked in the Superpole Race, but it didn’t work in Race 2. Alvaro improved and came back very strong again. It wasn’t easy to pass him in Race 2, but I kept fighting for the win.
“In the last three laps, the front tyre started to lock. I said second place was enough. Every lap, I caught him, and, on the exit of the last corner, he got ahead again on the straight; his bike is very fast.”