Andrea Atzeni timed things to perfection aboard Defoe to win the Al Zubarah London Gold Cup at Newbury.
Roger Varian's 8-1 chance had the far rail for assistance as the grey colt was nudged clear of long-time leader Mucho Applause deep inside the final furlong.
Defoe showed plenty of resolution at the death to claim the mile-and-a-quarter handicap by a length and a quarter from Mucho Applause. Time To Study was third.
Atzeni said: "The boss was very keen to make plenty of use of him from stall one.
"He put his head down and was always going to win the race.
"He stays well and he loved the ground. He's a horse that will get better as he gets older."
Varian said: "It's quite hard work out there for three-year-olds over a mile and a quarter on this ground, but he stays well and has a very good attitude.
"He was comfortable on this ground and it was a good performance.
"We'll see how he comes out of this race. I'll speak with his owner and we'll make a plan.
"It's been a bit frustrating with this horse at home. He's been ready to run for a month or so.
"He does need to get his toe in and it's been so dry, so we've had to be patient with him."
Visionary (4-1) held the late challenge of Simmie by a head to claim the Listed honours in the Shalaa Carnarvon Stakes.
Several horses were in with a chance a furlong from home, but Jamie Spencer took charge on Robert Cowell's colt and just had enough in the tank as Simmie closed as the line approached. Florida Times was third.
Spencer said: "He's a very lazy sprinter and he just idled in front - he almost gave it away.
"I've ridden him twice and won on him twice so he's been good to me."
Owners Al Shaqab Racing sponsored the Lockinge card at Newbury and enjoyed a winner when Denaar neatly justified 2-1 favouritism in the Olympic Glory Conditions Stakes.
Richard Hannon's youngster caught the eye under Frankie Dettori to preserve his unbeaten record with a three-quarters-of-a-length defeat of Starlight Mystery.
Dettori told Racing UK: "He coped with the ground, but this tested his stamina, big time, and I think his bravery got him there.
"He'll probably end up in the Coventry (at Royal Ascot).
"He tries very hard and I'm sure there'll be a nice race in him."
Natavia holds an entry in the Investec Oaks at Epsom and is now as short as 14-1 about winning the Classic on June 2.
Charlton said: "I've a big smile on my face, really. Winning any race is great, winning a stakes race for a big owner like Juddmonte Farms, who bought this filly, is very exciting.
"Like a lot of trainers, I was worried about the ground. We've seen some funny results and it's tough out there. It was very pleasing.
"Her work has been very good and it's not my normal pattern to go from maiden to a race like this, but I felt if she couldn't win this then we could always drop back to a maiden.
"The ground has affected the others a lot. They were well spread out."
Withernsea (12-1) got up close home to land the Toronado Handicap and give trainer Richard Fahey a double following his success with Ribchester in the Al Shaqab Lockinge Stakes.
Paul Hanagan brought the six-year-old with a strong run to collar the wayward Brigliadoro by a length. Mutarakez was third.