Broome rounded off a week of Classic trial domination for Aidan O'Brien with a stylish victory in the Derrinstown Stud Derby Trial at Leopardstown.
Hot on the heels of wins for Sir Dragonet, Circus Maximus and Anthony Van Dyck, the Donnacha O'Brien-ridden Broome was sent off the 2/5 favourite to enhance his own Epsom claims, having impressed first time out in the Ballysax Stakes over this course and distance.
His supporters could have been forgiven to having a nervous moment or two rounding the bend as he was niggled along a touch, but the son of Australia made ominous progress from two out and was well on top with 100 yards to travel.
He ultimately ran out a smart two-and-a-half-length winner from stablemate Blenheim Palace, who kept on well after cutting out the early pace.
O'Brien said: "We're delighted. He's lazy and that's his way of racing. Donnacha wanted to put him in there and race around tight on the rail. If he's going to the Derby that's what could happen to him.
"We were very happy. He's lovely and lazy and responds only when you want him. I think going to the line he was starting to stretch."
Asked if the winner could even be a St Leger horse in time, O'Brien added: "I'm not sure he'd stay that far, even though he looks like he'll stay there.
"It's more lazy he is than anything. If you look at where he was turning in, he got there very quick. He did well to make up the ground and before Donnacha got there he knew he was there in plenty of time.
"The plan was always the three races for him and he's run in two of them so far."
O'Brien reported Sir Dragonet and Anthony Van Dyck to be in good shape after their efforts at Chester and Lingfield respectively - and confirmed yet another Derby contender, Japan, on course to run at York on Thursday.
He said: "They seem to be fine. Anthony Van Dyck will improve plenty from the run.
"At the moment the Dante is the plan for Japan. We were trying to give him as much time as we could. We were going to come here and then we felt another week might help him again."
Sky Bet reacted by cutting Broome to 7/1 from 9/1 for the Investec Derby on June 1 and the firm's Michael Shinners said: "Aidan O'Brien has won just about every recognised trial this spring and while Broome didn't quite make the impression of Chester Vase winner Sir Dragonet, he's clearly a very smart colt and looks the type to appreciate a mile and a half at Epsom."