The New Zealand native and Ringwood Sky Boy topped the overall standings after an enthralling day of equine cross-country action at Burghley House, near Stamford.
Price had trailed 62-year-old fellow Kiwi Todd following the dressage, but the five-time champion’s leading horse Kiltubrid Rhapsody was eliminated after he fell.
And after finishing just one second outside the optimum time of 11min 11sec on Ringwood Sky Boy, Price said he is feeling confident ahead of the competition’s climax.
“You have to go out and bring your best game to the table,” he said. “I’m really happy with the one-second time penalty as he’s not a fast horse by his speed.
“He’s sometimes been a bit disorganised in the past and he can tend to do that, but I’ve learnt how to ride him, and he knows me as well as I know him.
“I just wanted to do as good a job as possible and not really think about the clock other than hearing a few beeps in the background coming and I didn’t leave anything out there.
“I’m very confident, I’m very happy with the last two days, it’s a journey and what I’ve learnt over the year at these big competitions is you have to treat each day as it comes.”
With the dressage and cross-country concluded, Sunday’s final day of action will see the riders tackle the show jumping trials at the prestigious four-star event.
But while Marlborough-based Price is in prime position, he is under pressure from reigning champion Oliver Townend, who finished inside the optimum time on Ballaghmor Class.
They were just one of four combinations to achieve that feat, along with five-time winner Andrew Nicholson, who sits in fifth on four-star first-timer Swallow Springs.
“I’ve always liked this horse and I’ve always had a lot of faith in him,” said the Marlborough-based six-time Olympian, who is also in eighth on Jet Set IV.
“He’s had his mishaps, it’s easy to remember those, but when I’ve ridden him like I’ve stolen him, he does the business, he gallops, he skips over ground.
“I knew when I got to one and two minutes and I was on time, you know you are going at the correct speed. I kept it up and I didn’t ease up on him, I kept him bowling along.
“The ability he’s got to jump out of pace makes a big difference and it makes it much easier to ride.”
Meanwhile, Marlborough-based rider Elizabeth Power is also in the mix on Soladun in seventh, having leapt up from 37th after the dressage by finishing inside the optimum time.
“It’s great to be back at this level and that was fantastic,” she said. “I wanted to get here and not ruin it early on, so I thought I’d give him a smooth run and not lose his confidence.
“I think it paid dividends in the end. I had loads of gallop left but I’ve never had him off the bridle before, so it was different feeling for me.
“I knew I had the time towards the end to make sure I did the fences properly and then when I jumped the last I realised how good it was and I was delighted.”
Oaksey’s Dan Jocelyn also made it round the course successfully on Dassett Cool Touch to move up to 32nd, but Lissa Green withdrew while Gubby Leech was eliminated.
Family-friendly Burghley is one of two UK-based four-star events and one of only six in the world, with 160,000 people and the best equestrians on the planet descending on Stamford for the week’s action.
The multi-award-winning Land Rover Burghley Horse Trials from August 30 – September 2 has been established as a major international equestrian and social event in the Autumn Sporting Calendar for over 50 years. For more information visit burghley-horse.co.uk