Aidan O'Brien's faith in Auguste Rodin was rewarded in Derby-winning style at Epsom, while Frankie Dettori's farewell tour witnessed another Oaks success for the veteran rider.
A bitter disappointment in the 2000 Guineas at Newmarket, Auguste Rodin was usurped as favourite for Derby glory before the off but he dominated on the track to give his trainer a record-extending ninth success.
Meanwhile in The Oaks, the irrepressible Dettori brought home Soul Sister for the seventh and final success of his career in the fillies' Classic.
Given that Aidan O'Brien has suggested he might be a Triple Crown contender, Auguste Rodin's comeback in the Guineas was a huge letdown.
The Ballydoyle handler told anyone that would listen that his colt was back working well at home and that good ground and a longer trip would see him shine at Epsom, but he drifted before the off and was 9/2 when breaking from the stalls under Ryan Moore.
O'Brien's other pair, Adelaide River and San Antonio, took the field around Tattenham Corner and into the straight, but 66/1 outsider King Of Steel burst out of the pack under Kevin Stott to threaten a massive upset for trainer Roger Varian.
Moore and Auguste Rodin got out after them and there was an inevitability in the final furlong as they got by to win, a first for the rider since 2013 and his third overall.
"He came with a massive reputation as a beautiful horse but he kept stepping up to all the markers all the way which is very unusual," O'Brien said. "He's totally unique that he's out of one of the greatest Galileo mares [Rhododendron] and by the greatest stallion in Japan."
Auguste Rodin earned a quote of 5/1 for next month's Eclipse at Sandown after his Derby win.
There was no third Derby for Dettori but he still managed to have a major say on proceedings with three victories at the meeting.
On Friday, he guided Emily Upjohn to a peerless success in the Coronation Stakes – enough to see her installed as 7/2 favourite for the Eclipse, before doubling his Group 1 tally with Soul Sister in The Oaks for .
Like Emily Upjohn in the same race a year ago, Soul Sister was slow to break from the gates but she was navigated to the outside of the field rounding Tattenham Corner and, when the ground started to level out, Dettori's filly bounded clear to win with authority from 5/6 favourite Savethelastdance.
"If I stayed on one more year, I may get close to Lester Piggott's 30 Classic wins," he said, before quickly pouring cold water on the possibility of extending his career. "I'm joking! It's incredible and I've had some fantastic rides."
Dettori was out of luck in the big race as Arrest toiled, but he did secure a victory on his last Derby Day as he steered Prosperous Voyage to success in the Princess Elizabeth Stakes, his final ride on the afternoon and, after which, he kissed the Epsom turf when confirming he wouldn't be back at the Surrey track again this season.
"My last one! And we won. To finish on a winner after riding here over 30 years is brilliant. I'm going to enjoy it," said the rider.
The George Boughey-trained Navello took advantage of the perfect run up the Epsom straight to prevail in a thrilling finish to the Aston Martin Dash Handicap.
Billed as the fastest five furlongs in wold racing, the 20-runner field careered around Tattenham Corner with Andrea Atzeni in a perfect stalking position behind a typically frantic pace.
Navello registered a short-head success ahead of the Middleham Park Racing-owned duo of Silky Wilky and Clarendon House for the minor honours.
Boughey said: "This has been a bit of a long-term plan. He likes fast ground and he is improving. The strong pace really does suit him, but he's hit the line well. He doesn't quite get six, but he gets a stiff five and you can't get much stiffer than here."
After his ninth Derby win, O'Brien drew plenty of plaudits from his peers in the training ranks.
John Gosden, who saw Arrest finish tenth having started 4/1 favourite, said the confidence in Auguste Rodin was telling, while also paying tribute to the runner-up.
"It was a brilliant achievement from Aidan to get the horse back from the Guineas because obviously something went wrong there. He had a hell of a target to reel in King Of Steel and it was some race; two proper horses," said Gosden. "The confidence Aidan had in his horse you don't ignore – it's as simple as that."
Sir Michael Stoute supplemented Passenger after a luckless Dante third but his charge was 12th and he, too, was fulsome in his praise for the winning trainer.
He said: "We know Aidan is a genius – he hasn't got to keep telling us, but he is!"