She was a granddaughter of Feola, a British broodmare foaled in 1926, who has been the female-line ancestor of numerous major winners including Pebbles, Deep Impact, Aureole, Nashwan, Jet Ski Lady, and Johannesburg.
His form in staying races had him start second favourite for the Group One Grand Prix de Paris over 3100 m on 25 June, but he ran poorly and finished unplaced behind Pleben.
In the Prix Jean Prat over the same course and distance later that month, he started second favourite and looked the likely winner early in the straight before being overtaken in the closing and beaten easily by the British-trained five-year-old Parnell with Filandre and Pleben in third and fourth.
[2] Lindley was again in the saddle when Lassalle was sent to England in June to contest the Gold Cup over two and a half miles on soft ground at Royal Ascot and started the 2/1 favourite.
His six opponents included the dual Irish classic winner Pidget, Celtic Cone (Yorkshire Cup) and The Admiral (Henry II Stakes).
Although Timeform acknowledged that the French colt had won in "grand style", they described the field as one of the poorest ever assembled for Britain's premier staying event.
After moving up to challenge for the lead early in the straight, he finished second, beaten a "short neck" by Parnell with a gap of four lengths back to Forceful in third place.
Parnell, however, had hung to the left in the straight, hampering both of his main rivals and the racecourse stewards relegated the British challenger to third, awarding the race to Lassalle.
He looked less than fully fit on his seasonal debut in April and finished fourth behind the four-year-old Recupere, Parnell, and Filandre in the Prix Barbeville.
[7] No International Classification of European two-year-olds was held in 1971; the official handicappers of Britain, Ireland and France compiled separate rankings for horses which competed in those countries.
[5] In the following year, the independent Timeform organisation gave him a rating of 120, making him 14 lb inferior to their top-rated three-year-olds Deep Diver and Sallust.
[7] In their book A Century of Champions, based on a modified version of the Timeform system, John Randall and Tony Morris rated Lassalle as an "inferior" winner of the Gold Cup.