Six Nations chiefs are negotiating the biggest sponsorship deal in rugby history that would provide the tournament with a £100million injection over six years. With headline sponsors RBS ending their 14-year deal after this year's event, CEO John Feehan and his team are narrowing down the shortlist of bidders. RBS pay £11m per year for the rights, but Sportsmail understands their successor could pay close to £17m — a 55 per cent price hike — between 2017 and 2023.