Colin Turkington admits his hopes of becoming a two-time British Touring Car champion this year have effectively been dashed by his clash with Mat Jackson in the Silverstone finale.
Turkington, the 2009 BTCC champion, led the race in his WSR BMW until a safety car eradicated his lead, and Honda's Gordon Shedden passed him soon after the restart.
As he struggled with his car's balance on the soft-compound tyre, Turkington fell down the order to fourth, and became embroiled in a battle over fifth place with the Motorbase Ford Focus of Mat Jackson.
After swapping places with four laps to go, Jackson then hit Turkington from behind at Copse, breaking his right-rear suspension and spinning him round.
Turkington's failure to score meant he dropped to 48 points behind runaway leader Andrew Jordan, with just the Brands Hatch finale remaining.
"It's a kick in the nuts - really frustrating when someone who's not in the championship battle effectively ends mine," said Turkington.
"It would have been a bit easier to accept if I'd been scrapping with the front four guys, and there had been a coming together and I came off worst, but Mat had nothing to gain from the move and that's what is hard to take."
Jackson, who apologised to Turkington straight after the race, received a £500 fine and three penalty points for his part in the incident.
"I can understand that he didn't mean it, but a bit more sympathy about how delicate my championship situation was would have been good," added Turkington.
"The only upside is that the car wasn't totalled - it wasn't very nice to end up facing the traffic at the exit of Copse, I thought that was it for me!
"I would have been happy with sixth, but now it's gone and I'm a rank outsider. It was going to be hard enough as it was.
"Although I can mathematically do it, the car won't be significantly quicker than everybody else for me to be able to overturn that many points.
"I'll be fighting back at Brands Hatch, but realistically now my aim is the top three."
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