Mostahdaf, Paddington and Kinross are among the big names declared for what promises to be an enthralling afternoon for British Champions Day at Ascot on Saturday.The John and Thady Gosden-trained Mostahdaf is one of the nine contenders for the Qipco Champion Stakes, in which the five-year-old will be bidding for a third consecutive Group One win having landed the Prince of Wales's Stakes over the 10-furlong course and distance back in June before adding the Juddmonte International at York to his tally.However, connections have expressed concerns about the likelihood of testing ground in Berkshire and he could yet bypass the race.The Champion Stakes field also features last year’s winner winner Bay Bridge and third-placed My Prospero, while French raider Horizon Dore is the favourite after winning each of his last four starts.Frankie Dettori teams up with King Of Steel on what is set to be his final afternoon of European action before embarking on international engagements and an eventual move to America.He now rides 2000 Guineas victor Chaldean for Andrew Balding in the Queen Elizabeth II Stakes after Inspiral was taken out, in what promises to be another intriguing one-mile clash.The Aidan O’Brien-trained Paddington beat him nearly four lengths in the St James’s Palace Stakes at Royal Ascot and he seeks a fifth Group One win after his unbeaten run came to an end at the hands of Mostahdaf at York.Tahiyra adds further spice, with Dermot Weld’s filly having won the Irish 1,000 Guineas, Coronation and Matron Stakes on her last three starts.Nashwa runs over a mile instead of tackling the Champion Stakes, with Big Rock and Facteur Cheval both leading contenders for France.The Dettori-ridden Kinross faces 14 in defence of his