Shane van Gisbergen has confirmed his dominance in the Supercars championship, flying past rookie pole-sitter Zak Best for his 12th win of the season.

Supercars championship leader Shane van Gisbergen has powered to his 12th win of the season, flying past surprise pole-sitter Zak Best.

Ford wildcard Best, 20, secured the first pole position of his fledgling career for Saturday's race at Tailem Bend.

But van Gisbergen asserted his dominance over the rookie with a long first stint at The Bend Motorsport Park in South Australia, passing Best on lap-11.

Van Gisbergen was able to extend his lead in the championship standings to 318 points with a strong drive to finish ahead of Ford veteran Will Davison and reigning Bathurst 1000 champion Chaz Mostert.

The 33-year-old is charging towards back-to-back titles and his third overall.

"The car was magic," van Gisbergen said after the 66th win of his Supercars career.

"We had to run long to gain clear air.

"(The tyres) were still fine... Will had passed us, we had to make that speed.

"The pit stop was awesome, too."

Best, who was competing in a Supercars championship event for just the second time, finished fifth in a promising result for the Tickford driver.

The youngster, from Benalla near Winton Raceway, was blown away by his performance in qualifying.

"I wasn't expecting this," Best said.

"I don't really know what to say.

"I didn't think I'd be on pole this afternoon."

Two 24-lap races will complete the event on Sunday.

SUPERCARS OTR SUPERSPRINT RACE ONE

1. Shane van Gisbergen (Holden)

2. Will Davison (Ford)

3. Chaz Mostert (Holden)

4. Cam Waters (Ford)

5. Zak Best (Ford)