• International winger Sean Lamont is helping to front Scottish Rugby's new sponsorship agreement with Guinness, which sees the brand become an official partner Picture: PA
Scottish Rugby's chief executive Gordon McKie said: "We are delighted to welcome Guinness to our family of blue-chip sponsors. Guinness has a rich pedigree as a sponsor of rugby union and we believe it underlines the confidence of the business community in Scottish Rugby that we have been able to secure this partnership.
"We look forward to working with Guinness in the exciting period that lies ahead. A key element of our partnership will be to promote responsible drinking."
Guinness, which already enjoys sponsorship rights in Irish rugby, has also announced deals with the RFU and Premiership in England and the WRU in Wales.
The brand's new sponsorship within the three nations will be augmented by a rugby campaign fronted by Scotland winger Sean Lamont, England flanker Lewis Moody and Wales' full-back Lee Byrne.
John Roscoe, Guinness GB's marketing director, said: "A pint of Guinness with your friends is the perfect accompaniment to a game of rugby and has been for a long time now.
"These new partnerships will give us our largest-ever presence in rugby and demonstrate our long term commitment to the sport."
The SRU has an existing partnership with Carling, the official lager and beer partner of Scottish Rugby, the Scotland international team and the Emirates Airline Edinburgh 7s.