The Scottish Premiership (referred to as the Tennents Premiership for sponsorship reasons) is an amateur league competition for Scottish rugby union clubs. First held in 1973, it is the top division of the Scottish League Championship. The most recent (2019) champions are Ayr, while the most successful club is Hawick, who have won the competition twelve times. Ten clubs contest the league, with the bottom club relegated to the Scottish National League Division One and second-bottom club involved in a play-off. The top level of club rugby in Scotland are the two professional teams – Glasgow Warriors and Edinburgh Rugby – that play in the United Rugby Championship. They assign their players to the clubs below in a Pro-Draft; so that they can still play when not used by the professional sides. From season 2019–20 a semi-professional championship in Scotland, known as the Super 6, was introduced – its teams no longer taken part in the Premiership competition. The Super 6 format is intended to bridge the gap between the amateur grade and the professional United Rugby Championship teams. History Up to season 1972–73, Scotland's rugby union clubs participated in what was known as the Scottish Unofficial Championship. It provided very unbalanced competition: some clubs played more fixtures than others and some fixture lists provided stiffer opposition than others. The resulting league table at the end of each season gave a very unbalanced and difficult-to-comprehend set of results. Starting in season 1973–74, the Scottish Rugby Union organised the full member clubs into six leagues. This suited some of the 'open' clubs but many of the older former pupils clubs found it difficult to compete successfully and were forced into going 'open' themselves to try to recruit some of the better players. Those that didn't declined. Open clubs kept their old FP or Academical name, and still played on grounds owned by the schools. In the first 14 seasons of league rugby the Division I championship was won by Hawick on ten occasions. One consequence was soon apparent: fewer players were selected from English clubs to represent Scotland. For the first time since before the First World War, the domestic game was producing an adequate number of players of genuine international class. Though the SRU's administrators were often seen as backward looking, Scotland had a national league before England, Wales or Ireland. Heriot's FP became the first city club to win the championship, they had already attracted "outsiders"; their leading try-scorer was Bill Gammell, a Fettesian already capped for the Scotland national rugby union team while playing for Edinburgh Wanderers. League rugby drew the crowds, and the 20 years that followed its introduction were the best in the history of Scottish club rugby. In that period the title of champions rarely went out of the Borders: with Hawick, Gala and Melrose enjoying long periods of ascendancy. Recently, however, the Borders domination has faded and Glasgow Hawks won the title three times in successive years between 2003 and 2004 and 2005–06. Since the advent of the leagues, the Scottish Rugby Union and its member clubs have re-organised the competition several times, usually to change the number of teams. The top Scottish clubs qualified to the British and Irish Cup from 2009 to 2014.