Ash Sutton's British Touring Car Championship title defence gathers pace after the Subaru driver stormed to his fifth win of the 2018 season during a wet opening race at Knockhill.

The Subaru Levorg driver started the opening race from eighth on the grid, but took full advantage of the torrential rain and scythed his way through the pack to eventually take the win ahead of current points leader Colin Turkington.

With pole-man Dan Cammish leading much of the opening half of the race, Sutton worked his way through the BMW contingent - comprising of Stephen Jelley, Andrew Jordan and Turkington - before moving into the lead on the 12th lap of the race.

Once Sutton disposed of Cammish, the reigning champion immediately bolted away and quickly established a near six-second lead ahead of the chasing pack.

However, contact between Turkington and Jelley at Clark corner on the 19th lap of the race triggered a safety car and subsequently wiped all of Sutton's advantage away.

The incident between the two BMWs meant Jelley suffered a heartbreaking end to his podium hopes after his race ended abruptly in the gravel trap as a result of the contact from Turkington.

Turkington gained a superior exit to Jelley on the run up to Clark corner but made contact with the rear of the Team Parker Racing BMW.

Of the incident, Turkington said: “I sincerely feel sorry for Stephen and I can assure you there was no intention.  The BMW was well balanced and we were strong in most places despite the standing water.  It was a busy race and I was enjoying the cat and mouse action going on.”

Following the restart on lap 24, Sutton retained his position with little opposition, as Turkington settled for second, while Cammish completed the podium order for Honda in third.

Jordan was fourth aboard his BMW Pirtek Racing 1 Series, while a late charge saw Josh Cook rise up to fifth, ahead of Tom Ingram and Tom Oliphant in sixth and seventh.

Despite threatening the sharp end early in the race, Chris Smiley ended the opening encounter in eighth, as Adam Morgan finished ninth ahead of home hero Rory Butcher in tenth.

Standing in for his injured dad Rob, Ricky Collard scored his first points in the series with a strong drive in eleventh place.