Aidan O'Brien believes stamina is Capri's forte as the Irish Derby hero spearheads a four-strong Ballydoyle assault on the William Hill St Leger at Doncaster on Saturday.
O'Brien has won the world's oldest classic four times and his 2017 team also includes Venice Beach, Douglas Macarthur and The Anvil.
"Capri is a horse we always thought would stay further than a mile and a half and he's in good form," the champion trainer told At The Races.
"He had a break after the Irish Derby. We were playing with the idea of running him in the Voltigeur, but we knew that he would have a 5lb penalty and his scope wasn't 100%, so we just decided to leave him.
"The Irish Derby was a very truly-run race. He was handy all the way, he kicked and kept going. I don't think he was relenting at the line."
Venice Beach goes to Town Moor on the back of playing second fiddle to the impressive Cracksman in the Great Voltigeur Stakes at York.
"Venice Beach is a horse we always thought would stay further than a mile and a half as well," said O'Brien.
"He had a very good run in France and we gave him a little bit of an easy time going to the Voltigeur, kind of using it to bring him on for the Leger, rather than the Voltigeur being the be-all and end-all.
"He ran a good race and he will have come forward. We look forward to seeing him the next day."
Douglas Macarthur has a bit to find after finishing fourth in the Voltigeur, but O'Brien is expecting an improved performance.
"Douglas Macarthur had an easy time after the Irish Derby and we were also using the Voltigeur as a stepping stone to Doncaster for him," he said.
"He's well and we were very happy with his run. We put a hood on him so that he would be relaxed when we went a mile and six with him."
The Anvil has been well beaten in the English and Irish Derby since finishing third to Venice Beach in the Chester Vase.
"The Anvil is a straightforward, solid horse who likes nice ground. He'll stay a mile and six and might even stay two miles," said O'Brien.
O'Brien's son Joseph saddles Rekindling, and said: " He's in good form and gets the trip well. He ran well the last day at the Curragh. We're just hoping the ground isn't too soft for him. It's a very good race but we're hopeful."