The deal means that all the action from the Magners League, involving Edinburgh and Glasgow Warriors, will feature on a new one-hour highlights show at 5.30pm on Sundays called STV Rugby.
The programme brings together two of the biggest names in Scottish Rugby. The presenter will be former Scotland captain Andy Nicol, and alongside him will be regular co-host and fellow ex-internationalist Scott Hastings.
In addition, the deal features live coverage of both Magners League 1872 Cup games between Edinburgh and Glasgow Warriors over the Christmas and New Year holiday period.
Scottish Rugby's Chief Executive Gordon McKie said: "This is tremendous news. It's a wonderful opportunity for Scottish Rugby to have our sport back on free-to-air television on a regular basis.
"The game needs the oxygen of television coverage. Edinburgh were runners-up in the Magners League last season and Glasgow Warriors enjoyed some spectacular victories. Regular television coverage and related online promotion by STV can let a bigger audience see what these two teams have to offer and act as the catalyst for larger attendances at their grounds.
"Coverage can also make the pro-teams a more attractive commercial proposition and offer additional reward to our sponsors for their investment," he declared.
David Jordan, Director of Celtic Rugby, the body that oversees the Magners League, hailed the news. He said: "This is great news, not just for rugby fans in Scotland, but it allows Magners League rugby to be displayed throughout Scotland and will add significant value to our competition.
"STV is joining us at an exciting time with the introduction of play-offs which is bound to make the tournament even more compelling viewing right through to end of the season."
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