Babouche returned to her devastating best with an authoritative display in the Goffs Lacken Stakes at Naas.
Ger Lyons' filly was a Group One winner at two in the Phoenix Stakes, where she beat Whistlejacket, but had been below that form when beaten in the Cheveley Park and when disappointing on her return to action this season at Cork.
With that run under her belt, though, she looked a different proposition in the hands of Colin Keane.
She again faced Whistlejacket, who had scored on his seasonal debut and was sent off an odds-on favourite.
However, Babouche (2-1) always looked to be travelling better and Ryan Moore was soon at work against the rail on Whistlejacket.
Once Babouche was asked to quicken, she did so immediately and ran out a two-and-three-quarter-length winner from the favourite.
She is now the 4-1 favourite for the Commonwealth Cup at Royal Ascot.
"That's the first time I've seen that this year from her," said Lyons.
"I'm delighted with the team's performance. We sucked it up and we went to Cork, it wasn't the obvious right thing to do but it was the right thing to do for what I was seeing at home.
"We parked the reputation and the ego and we said 'right, go down there, you're going to get beat because it's a furlong too short for you. We've spent the whole spring trying to settle you down and doing it right'. Now she's back.
"Now we can go to the Commonwealth and if we get beat, we get beat, but at least we know we are locked and loaded. It's been a good day."
He went on: "She's a Group One winner but she hasn't been doing that. I was delighted with what I've seen because it was a work in progress, but I needed to see that, otherwise we weren't going anywhere - we've won our Group One, so there's no point in carrying on.
"Now we can go off to the Commonwealth, it doesn't mean we'll win it but we're going there with a huge chance.
"When I saw him (Whistlejacket) in Navan and I saw her at home, I wasn't beating him, so then I said 'lads, we have to do something'.
"If I rock up in the Lacken without Cork, we wouldn't have done that. It's brilliant, it's worked. Sometimes we get it right!"
Lady Iman maintained her unbeaten record and was made clear favourite for the Queen Mary and the Albany Stakes at Royal Ascot following her ultimately cosy victory in the Coolmore Stud Irish EBF Blackbeard Fillies Sprint Stakes.
The Ger Lyons-trained juvenile looked to face a stiff task on paper up against Aidan O'Brien's Simply Astounding, a Wootton Bassett filly out of Minding who had been very impressive on her debut.
However, the odds-on favourite was one of the first beaten, with Colin Keane on Lady Iman setting sail after Green Sense inside the final furlong, another unbeaten filly.
While it did take a while for Lady Iman to get on top, she always looked like getting there and crossed the line with three-quarters of a length to spare.
She is now 4-1 favourite for the Albany and the same price for the Queen Mary.
"She came to me with a reputation and she's done everything easy," said Lyons.
"Colin said she gets to the front and she idles, which is lovely. I asked the question where to now and Colin said 'wherever you want'.
"We'll sit down with Tony and Roger (O'Callaghan), it's all about the sire and doing the right thing by the filly going forward.
"You don't rule anything in or out. There are plenty of nice races here.
"People have to put guns to my head to get over there (Ascot). I'll do whatever I'm asked to do by the owners but at this moment in time, we'll sit back.
"She had Queen Mary written all over her but it's not the be all and end all."
When asked if she was still improving, he added: "You don't know until they don't. We're right and wrong about horses week in and week out.
"She's doing everything easy, so we'll keep taking it and keep taking what I can at two.
"Who knows, she could be the next filly to win a Phoenix."
Charles Darwin justified short odds in the Coolmore Stud The Antarctic Race over five furlongs to stay on course for a trip to Royal Ascot.
Debutant Cardiff By The Sea, a 320,000 guineas buy at the breeze-up sales, briefly threatened to make a race of it at the furlong pole, but the 1-14 favourite ultimately sprinted clear to prevail by three and a quarter lengths under Ryan Moore.
The son of No Nay Never is a full-brother to Prix Morny and Middle Park victor Blackbeard and was a fourth straight winner of this race for Aidan O'Brien, with subsequent Coventry Stakes scorer River Tiber among the previous trio.
Having already got off the mark at Navan three weeks ago, Charles Darwin remains the ante-post market leader for Ascot's Norfolk Stakes next month.
"We're very happy, he just needed a nice sharp bit. Obviously the plan is to go to Ascot with him and it was nice to do it on lovely ground," said O'Brien.
"Ryan was very happy with him, he's still babyish and I suppose he's been doing everything so easy. Obviously when he goes to Ascot, he won't have much time for learning.
"Hopefully that will have done the job and we'll just look after him between now and then."
When asked if the Norfolk was the target, he added: "Probably. That could change, it will depend on what the lads want to do, but I'd imagine it's very likely.
"Albert Einstein might run next weekend and we always thought he could be a Coventry horse, we thought this could be a Norfolk horse but he needed to learn. He was green and babyish and he has to be just caught hold of today. That's why we were here with him and we're delighted."
Copacabana Sands (18-5) gained compensation for an unlucky run at Leopardstown last time when storming home to claim the Listed Owenstown Stud Stakes over seven furlongs for Michael O'Callaghan.
Market leader One Smack Mac made a bold bid from the front but could not resist the winner's final flourish, with Jamie Powell getting his mount up by half a length.
"Luckily, Jamie manoeuvred his way out," said O'Callaghan. "To be fair to him for riding his first stakes winner, and to be an apprentice still with a claim, he was very cool and gave her a great ride.
"He pulled his stick through at the right time when he got out and she's hit the line strong.
"She jumped and travelled and everything panned out exactly how he said he wanted to ride her.
"It's a huge day for the filly as she has a nice pedigree and now she's broke her maiden in a Listed race.
"She's shown that she has ability before now. We only picked her up in February and she's done nothing but go from strength to strength, and improve."
One Smack Mac's connections, Ger Lyons and Colin Keane, enjoyed better fortune as Beckman upset odds-on favourite Mississippi River in the Royal Ascot Trials At Naas Handicap, powering past in the latter stages of the mile contest to oblige by two and a half lengths at 7-2.
"It was a nice surprise, I was disappointed with the previous one getting his pocket picked. They are very similar horses," said Lyons.
"I thought that was a nice effort, I loved how he quickened away when he got the gap. He's a fun horse to have, honest as the day is long, so we'll enjoy him."
