After the power of the 4-year-old Baaeed in the Queen Anne (G1), there was a real yearning around Ascot to see a miler from the classic generation throw down the gauntlet.
Coroebus was always the most likely, and while a finish of heads, short heads, and necks would suggest there were no fireworks, the son of Dubawi found a different way to win June 14 after being trapped in a pocket until halfway up the Ascot straight.
He will have learned more about being a racehorse in a shade under 100 seconds of the St James's Palace (G1) than in any of his four previous career starts.
William Buick thumped his chest and pointed to the crowd a couple of strides after edging out the gutsy 28-1 shot Lusail , the first sign of the pressure that had been ratcheting up inside him as Coroebus searched for a clean seam, which eventually opened up the inside rail.
"You have to enjoy these good horses and I'm very privileged to be able to get on them, but at the same time it's a case of getting the job done, and it was one of those races where it was tricky," said Buick, here reunited with Coroebus after having chased him home aboard Native Trail in the QIPCO Two Thousand Guineas (G1).
Buick briefly looked to switch right in the straight, but with daylight to be had, he sat tight and sure enough, Aikhal cracked on his inner and the escape hatch opened.
"A good draw can turn into a bad draw very quickly," Buick said. "He travels extremely strongly and you just want him to drop his head. In the straight I had no option to go until there was enough room, and then he picked it up and went through. He's got everything you could ask for in a racehorse."
Paddy Power eased Coroebus from 9-4 out to 3-1 for the Qatar Sussex Stakes and a collision course with Baaeed, but trainer Charlie Appleby was in no mood to duck Shadwell's world No. 1.
Appleby said: "We spoke beforehand about having Baaeed and Coroebus together and the Sussex is always a fantastic race, with the 3-year-olds and the older horses taking each other on.
"We wanted to be confident in doing that off the back of a win today, and I think that's still very much in the conversation. As always, we'll let the dust settle and I'll have conversations with His Highness (Sheikh Mohammed) and the team and we'll firm those plans up.
"But on the evidence of what we've seen today, he deserves to be there for sure."
Warming to the theme of pitching Coroebus into the fire at Goodwood, Appleby said: "Baaeed was a very impressive winner for sure. I'm taking nothing away from him. But don't forget that's only the fifth start of (Coroebus') career and I thought it was a gutsy performance in a race that probably wasn't run to suit us.
"Of course we'd all like to have more pace in a race or wish the race had been run smoother. The key thing I said to William was get that position and don't lose that position. Therefore he was always having to keep the revs under him and the horse was getting keener and keener. I just think that paid over the last 100 yards.
"We saw it in the Juddmonte Royal Lodge Stakes (G2), he shot clear, and then those last 100 yards, you've got to sit and you've got to count to 10 with this horse. And William gave him a brilliant ride round there. I just think that's possibly why he wasn't winning as impressively as one would have possibly like to have seen."
It was the fourth success for Coroebus, the 10-11 favorite, and the first away from Newmarket.
Appleby added: "That's going to be a big learning curve for him today in terms of the traveling and the walking around. He's never been more than 20 minutes up the road out of Newmarket. Those challenges have been put upon him and he's ticked the boxes."
My Prospero and Mighty Ulysses both threw down major challenges inside the final furlong, while Maljoom finished fast after getting no luck up the rail.
But in the end it was Lusail who, having been bested by Coroebus a furlong and a half down, fought back to almost get his head back in front.
"He overraced a little bit in the race," rider Pat Dobbs said. "I wish he'd have relaxed a bit better and saved a bit more energy for the end, but it was a massive run."
Trainer Richard Hannon added: "He was a good horse as a 2-year-old and he's proved his run in the Guineas was no fluke. I'm absolutely delighted. He's in the Sussex and the owners sponsor that, so that will be a target and it might just suit him."
Dobbs was given a four-day ban for using his whip in the incorrect place.