The four-year-old is set to have his last race in the care of Aidan O'Brien on Sunday, after being sold by Coolmore to Australian connections with the aim of going for the Melbourne Cup.
Third in last year’s St Leger at Doncaster, Southern France won the Irish St. Leger Trial at the Curragh last month.
O’Brien also has the last two winners of Britain’s oldest Classic, Kew Gardens and Capri, plus Cypress Creek and Western Australia among a list of 18 horses remaining at the confirmation stage as he seeks to win this race for a sixth time.
Last year’s Melbourne Cup victor Cross Counter and Ispolini represent Newmarket trainer Charlie Appleby – while Sylvester Kirk’s Salouen and Wells Farhh Go, from Tim Easterby’s stable, are other UK hopefuls.
Appleby’s unbeaten youngster Pinatubo heads 15 standing their ground for the Goffs Vincent O’Brien National Stakes.
Jessica Harrington has a powerful hand in the Moyglare Stud Stakes, with three Group-race winners to choose from.
The Moone handler has nominated Airlie Stud Stakes scorer Albigna as her most likely representative, but also has the option with Debutante Stakes victor Alpine Star and Cayenne Pepper – who took her unbeaten record to three in the Flame Of Tara Stakes.
The daughter of Kyllachy has lifted Listed, Group Three and Group Two races on her last three starts – and may now have her chance at the top level.
A strong British entry features Beverley Bullet winner Judicial, trained by Julie Camacho, Michael Dods’ Mabs Cross and Tate’s Invincible Army – who was fifth in the Haydock Sprint Cup at the weekend.
Joseph O’Brien’s Iridessa and the Aidan O’Brien-trained pair of Magic Wand and Pink Dogwood were the first three in the Pretty Polly Stakes at the Curragh in June, and could face each other again in the Moyglare ‘Jewels’ Blandford Stakes.
Others among 22 standing their ground for the Group Two over a mile and a quarter are the only British raider Nausha , from the Varian stable, and Dermot Weld’s Tarnawa, winner of the Give Thanks Stakes at Cork last month.