The streaming of the ad is part of an online deal booked by Initiative Media, which booked the offline campaign, that also includes banner ads across the Yahoo.co.uk site.
This is the first time a TV ad has been broadcast online in this way on a UK website. The ad runs with a response form to encourage feedback from viewers and is to be included in the Yahoo! group news email.
Andrew Cullis, brand manager for Vauxhall's Astra, said: "With our new Astra ad showing on TV at the same time and the reach of broadband in the UK now at the 1m mark, the timing for this new format is ideal."
The 30-second TV ad, created by Delaney Lund Knox Warren and which airs on UK TV screens until the end of the year, shows three identical Astra GSis driving in formation to the sound of a rollercoaster.
The cars drive through a series of locations including a road tunnel, around hairpin bends and weaving through a dark warehouse. The spot aims to compare the exhilaration and power of the Astra with a theme park ride.
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