The ad, created by Big Al's Creative Emporium, features Greenwood being rudely awakened in his house by a Las Vegas boxing compere with a microphone, surrounded by glamorous female dealers. Another version of the ad features former England cricketer Michael Vaughan.
The 30-second spots promoting the betting site's casino product launched on Friday on Comedy Central. They will run for 12 weeks, across the UK, Sweden and Denmark.
The casino will feature more than 180 games, including live dealer tables where customers can chat to the dealer while playing one of their favourite table games.
In August, Greenwood and Vaughan featured along with footballer Lee Dixon and horse trainer Paul Nicholls in an online video for Betfair, spoofing the 1990s Ferrero Rocher 'Ambassador's reception' campaign.
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