Not many Thoroughbred foals are inbred as closely as Bast, who has Arch 3x2 as the broodmare sire of her sire Uncle Mo and the sire of her dam Laffina. In her case, this cross builds on her second dam's being sired by 1992 Budweiser Irish Derby (IRE-I) winner St. Jovite to give a strong foundation of stamina, with the equally strong suggestion that she will be a better runner at 3 than 2---and quite possibly, better at 4 than 3 if she stays in training that long.
Bast's success at 2 is not necessarily a fluke, however. Her sire Uncle Mo was the American champion juvemile of 2010, and the aforementioned St. Jovite, though a top-class horse over a mile and a half at 3, was a champion at 2 in Ireland. Further, Bast comes from the female family of Quick Touch (by Count Fleet), which has produced its fair share of precocious runners.
While Quick Touch was bred for stamina, her primary gift to her three stakes-winning daughters (headed by 1958 American champion 2-year-old filly Quill, by Princequillo) was speed. Quill trained on to be a major stakes winner at 3 and 4 and proved a fine producer of staying runners as well, but her half sister Capelet (by the speedy Bolero) won the 1956 Frizette Stakes and afterward failed to distinguish herself further on the track. Her producing career reflected the form she had shown while racing as her best runner, Traffic (by Traffic Judge), won the 1963 Hopeful Stakes and did nothing after running second in the 1964 Gotham Stakes.
Nature, a stakes-placed half sister by Nashua to Traffic, was sounder and later-maturing but not as brilliant. She threw back to her speedy female line as a broodmare, with her best runner being 1979 Astarita Stakes (USA-III) winner Royal Suite (by Majestic Prince), who was also a runner-up in two Grade I events as a juvenile. Perhaps in an effort to breed more stamina back into the line, Royal Suite's winning full sister Majestic Nature was bed to St. Jovite, yielding stakes-placed St. Lucinda.
St. Lucinda did her best running on turf over intermediate distances and was listed-placed at both 2 and 3. She produced three stakes winners as a broodmare and was clearly at her best when bred to stallions with some demonstrated speed. Her best runner was Mananan McLir (by Royal Academy), who won the 2002 American Derby (USA-IIT).
Laffina, St. Lucinda's foal by Arch, apparently failed to pick up on the speed inherent in Arch's female family (that of 1983 American champion 2-year-old filly Althea) or in her own dam line and was probably simply too stamina-oriented to be very successful in American racing. For her, a sire with real speed was a necessity, and Uncle Mo certainly fit that bill even though many horsemen would have raised an eyebrow at the close inbreeding involved. Bast is the result of Laffina's first mating, and the mare has since produced a 2018 colt by California Chrome and a 2019 filly by Pioneerof the Nile before being bred back to Ghostzapper.
As previously noted, Quill---who as a daughter of Princequillo could be expected to stay---was both a top juvenile and a highly effective runner later. On pedigree, at least, Bast appears poised to follow the example of this distinguished member of her female family. If she does, then 2020---at least in the sophomore filly division---may well be the year of the cat.