The safety car was deployed to retrieve Turkington's car, and shortly afterwards Tordoff’s car ground to a halt with a mechanical fault. This left Austin and Shedden in second and third, although neither could catch runaway leader Neal, who secured his first victory for the best part of a year.
Jackson claimed fourth ahead of Plato, whilst the WIX Racing Mercedes of Adam Morgan completed the top six after charging from 17th on the grid.
In race two, Neal made a good getaway, but was adjudged to have jumped the start and was handed a drive-through penalty. Before he had chance to serve his punishment, Austin tried to overtake the Honda at the exit of turn one. His Audi A4 ran off the circuit and as he scrambled back onto the asphalt he made contact with Shedden, who spun and rejoined at the rear of the field.
Austin continued in third place behind Jackson and Plato, who moved up to first and second when Neal served his drive-through penalty. From that point on, Jackson was able to control the race in his Ford Focus, racking up the 20th victory of his BTCC career and the first in nearly two years.
Austin and Plato tussled for position throughout the contest but the places remained static for the duration.
Most of the action in the latter half of the race came as championship leader Turkington scorched through from the back of the field to finish fourth.
Nick Foster started from pole position for the reversed-grid third and final race. In the early stages of the race the eBay Motors driver fended off Fabrizio Giovanardi, Tom Ingram and Dave Newsham, but Foster's team-mate Collard made light work of the drivers ahead of him and closed in on the leader.
It didn't take long for Collard to move ahead, and Foster dropped behind Newsham, Ingram and Turkington. Ingram's Toyota Avensis was muscled out of contention, leaving Turkington and the resurgent Foster to challenge Newsham for second.
Despite fierce pressure, the Inverness-based driver resisted the attack, and in the closing stages Turkington had to concentrate on defending his third position from Foster.
Jordan and Shedden had a physical scrap on their way to fifth and sixth respectively, while Morgan took a solid seventh in his Mercedes.
The results from the Scottish track leave Turkington atop the points standings, pursued by Shedden and Plato.
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