By Racinguk.com staff
The Ascot Gold Cup winner adopted his usual front-running tactics under Frankie Dettori and appeared to have all of his rivals in trouble as he went in search of a third successive win in the race, which was newly-upgraded to Group One status.
However, Stradivarius, with Gosden keen to take advantage of the weight-for-age allowance as he was at the weekend with Enable in the King George, stayed on strongly.
Just like Big Orange, Stradivarius was a Royal Ascot winner in the Queen's Vase and the 13lb difference in weight was key inside the final furlong as the 6-1 chance pulled clear, with another three-year-old, Desert Skyline, in third.
Gosden has won the Leger in recent years with the likes of Lucarno, Masked Marvel and Arctic Cosmos and now all roads surely lead to Town Moor once more. The winner is now 4-1 second-favourite for the final Classic with Betfair.
"He's not the biggest and he got knocked around a bit, but Andrea has been cool today," Gosden said: "Frankie went into the middle which was clever as he didn't want to be attacked near a rail on one side, but that meant it opened up for us.
"I did say good luck to everyone going in, Big Orange has got a huge heart and has run with credit again, but he was running into a three-year-old now and not the older horses, who is getting 13lb from him.
"Yes, last year, it would have been 16lb so it has changed, but full marks to the horse and owner-breeder Bjorn Nielsen, who has put an awful lot into this game to get nice moments such as this, which don't come along very often.
"We go to the St Leger, which is a race that I love and it is one mile and six and a half furlongs around Donnie, which is probably a similar test as it is an open galloping track whereas here is all zig zags and bends.
"I am always frightened when you take on the older horses with a three-year-old in a race like this, I thought he'd run well and I could see him in the frame but not necessarily winning. He has a good turn of foot, which is a good weapon in a two-mile race.
"I don't think the three-year-olds have an enormous advantage - Enable is a brilliant filly and this is a proper stayer, you can't come and do it without a proper horse."
Atzeni was riding a Group-race treble after earlier victories on Expert Eye and Breton Rock. He also won the handicap that closed the card.
"This horse [Stradivarius] was getting a lot of weight off Big Orange and is still improving. I don't think he knows how good he is - he's a little immature and still learning. He'll be better next year. He doesn't know he's a racehorse.
"The main plan was to keep away from Big Orange - you can't get near him because he's a fighter. You have to race away from him. At the two-furlong marker, he was ahead of me but not going away and I knew I had him.
"I got a great run up the rails and he picked up really well - it's lovely to win a Group One. I'm very lucky to work for very good people, especially Roger [Varian] and Sheikh Mohammed Obaid, and when I'm not riding for them I'm fortunate to ride for people like Sir Michael [Stoute] and John Gosden."
Trainer Michael Bell was proud of Big Orange in defeat.
"We know he is better on faster ground, but the winner is probably a very good horse," he said.
"He pulled well clear of the older horses and the other three-year-old was third. That weight concession is very tough for older horses, but he has run a huge race and I'm very proud of him.