Luthier was a representative of the Byerley Turk sire line,[1] unlike more than 95% of modern thoroughbreds, who descend directly from the Darley Arabian.
[2] Riverqueen's dam Riverside was a high-class racemare who won the Prix de Royallieu in 1969 and a granddaughter of Refreshed, who finished third in the 1000 Guineas and was a half-ister of Festoon.
Apart from Suvannee, Antrona and Kesar Queen, the field included the 1000 Guineas winner Flying Water and Theia, the top-rated two-year-old French filly of 1975.
Two weeks later, Riverqueen was matched against older horses for the first time in the 2500 metre Grand Prix de Saint-Cloud, a race which had never been won by a three-year-old filly.
[6] Her main rivals in a seven-runner field were Ashmore (runner-up in the race in 1975), Maitland (Prix Jean de Chaudenay), the British challengers Quiet Fling (Coronation Cup) and Libra's Rib and the stayer Citoyen.
Following reports that she had defeated the four-year-old filly Ivanjica in a trial gallop she started 2/1 second favourite behind Pawneese in the Prix Vermeille at Longchamp on 19 September but ran very poorly, finishing ninth of the ten runners, almost twenty lengths behind the upset winner Lagunette.
[5] There was no International Classification of European two-year-olds in 1975: the official handicappers of Britain, Ireland and France compiled separate rankings for horses which competed in those countries.
The independent Timeform organisation, in their annual Racehorses of 1975 felt that there was insufficient data to award Riverqueen a rating but described her as "sure to go on to better things".