The clash between racing's superpower trainers ended with a 1-1 draw for Aidan O'Brien and John Gosden as they shared the biggest two races of a massive weekend for racing in Europe.
O'Brien landed a sixth William Hill St Leger at Doncaster with Ryan Moore-ridden Kew Gardens beating Gosden-trained favourite Lah Ti Dar.
But it was Gosden's Roaring Lion, ridden by Oisin Murphy, who then dramatically cut down Saxon Warrior in the Irish Champion Stakes at Leopardstown.
Roaring Lion might have been beaten by Saxon Warrior in the 2,000 Guineas but Gosden's grey colt has now beaten his old rival in the Eclipse and International Stakes and now Ireland's top 10 furlong race.
The honours being shared meant both trainers could reflect on a day with satisfaction. The 2018 season has been a difficult one for O'Brien by his own high standards with his stable struggling to shake off a mid-summer bug.
Twelve months earlier when Capri won the 2017 St Leger, it was one of O'Brien's 28 group one win in a record-breaking season.
Kew Gardens' win was O'Brien's eighth of 2018 and a first since the same horse won the Grand Prix de Paris at Longchamp on July 14.
But his dual group one strike sets up the possibility of an autumn charge by O'Brien, who is represented by Idaho, Cypress Creek and Flag of Honour in the Irish Leger at the Curragh this afternoon. A shot at the Arc could be on the cards for Kew Gardens, who won the Queen's Vase at Royal Ascot over a mile and three-quarters and has blossomed throughout the summer.
A run in the King George VI & Queen Elizabeth Stakes had been considered for the son of Galileo until he succumbed to the Ballydoyle bug and, despite being weak in the betting, his form credentials were more solid than Gosden's Lah Ti Dar, who had romped home by 10 lengths at York but lacked experience having only had three previous runs.
The difference showed on the track.
While Lah Ti Dar was being niggled turning into the home straight and took a while to become balanced under Frankie Dettori, Kew Gardens, now a veteran of 12 races, was a total pro and his two-and-a-half length advantage was never threatened after hitting the front two furlongs out. O'Brien, who also trained 20-1 St Leger third Southern France, said: 'He is a horse who has progressed well. We thought he would stay well and he has a lot of class.'
Moore said: 'He got there very easily. He is a very uncomplicated horse and has a fantastic attitude.'
Gosden was left to rue Lah Ti Dar's inexperience.
He reflected: 'That is the first real race she has had in her life. We been beaten by a proper St Leger horse but she has run an absolute blinder.'
Gosden will now plot a shot at the Champion Stakes at Ascot in October and possibly a challenge for the Breeders' Cup in the US for Roaring Lion, who produced a career-best display according to owner Sheik Fahad Al Thani.
While Lah Ti Dah just missed out on Classic glory, the hopes her stablemate and little brother Too Darn Hot can achieve it burn brighter after a performance laced with star quality which saw him land the Champagne Stakes under Dettori by a length and three-quarters from Phoenix of Spain.
Too Darn Hot, who like Lah Ti Dar carries the colours of owner, composer and theatre impresario Lord Lloyd-Webber, is 3-1 favourite for the 2019 2,000 Guineas and 7-2 favourite for the Derby with Sky Bet.
Dettori said: 'What he did between the three-furlong and one-furlong mark was pretty amazing.'
Upset of the day came in the Matron Stakes at Leopardstown where odds-on favourite Alpha Centauri, chasing a fifth successive group one win, failed by three- quarters of a length to haul in Karl Burke-trained 10-1 shot Laurens, who made all to win under Danny Tudhope, standing in for regular injured jockey PJ McDonald.