Muntahaa led home stablemate Weekender to provide John Gosden with a one-two in the Sky Bet Ebor at York.
It has been quite a week for the Clarehaven handler, having seen Roaring Lion dominate his rivals in Wednesday's Juddmonte International before star stayer Stradivarius landed a £1million bonus with victory in the Lonsdale Cup on Friday.
He saddled two runners in Saturday's £500,000 feature and both were to the fore as the field approached the final two furlongs.
Top-weight Weekender, ridden by Frankie Dettori, committed for home early, briefly racing into a clear lead.
However, Muntahaa (11-1) could be spotted travelling ominously well in behind in the hands of Jim Crowley and he came home best to win decisively by three and a quarter lengths.
Irish challengers filled out the places, with Jarlath Fahey's Sea The Lion third ahead of the Ger Lyons-trained Mustajeer in fourth.
Willie Mullins saddled the first two in the betting, but both Whiskey Sour and particularly 3-1 favourite Stratum suffered troubled passages and never threatened to land telling blows.
Angus Gold, racing manager to Muntahaa's owner Sheikh Hamdan Al Maktoum, said: "His ability was never in doubt. It was just a case of getting him in good form mentally.
"John said to me last week he had never had this horse better."
Asked whether a tilt at the Melbourne Cup could be considered, Gold added: "If entries haven't closed yet, we'll put him in. Whether he'd take to it mentally with the hustle and bustle, I don't know."
Former champion jockey Crowley said: "We could have had egg on our face. It was Mr Gosden's plan to stay out wide because he's quite a keen horse and he works very well on his own and he prefers to have his own space.
"I was drawn out wide - he had a car park badge - but we managed to go forward and get into a nice rhythm. I was lucky to get in on the bend. It was a very easy race to ride, really.
"I was always confident in the race. My only concern was not to get there too soon. When he hit the front he got on with it. He's a classy horse and is very well thought of.
"It's a nice pick me up after yesterday (with Battaash). We needed that."
Jarlath Fahey was delighted with the performance of Sea The Lion and is already eyeing a tilt at next year's Ebor, which will be worth £1million.
He said: "We're thrilled. When you hit the places at a meeting like this, it's unbelievable.
"He's a very good horse and runs his heart out.
"The way he's rated now, it's going to be difficult to find races for him. He needs quick ground and if the weather breaks we might not have anything for him for a while. We have no entries for him at the minute.
"We have no plans, but we might come back next year and try to win the million."