Adam Rolston squatted and measured his putt. The early evening sun at Mt Bogd Golf Club in Ulaanbaatar, Mongolia still hadn’t quite dried the moisture off the green, and he approached the ball tentatively. Two hundred spectators surrounded the green, including locals, close friends and family as he holed a seven-foot putt perfectly. The longest hole in golf had finished after 82 days and 20,093 shots across Mongolia.

Rolston has played many rounds of golf in his life, but he knows he will never complete a more satisfying scorecard. A former rugby international for Hong Kong, Rolston and his caddie Ron Rutland played the longest hole ever completed across Mongolia, covering 2,011km of difficult terrain, playing through the desert, icy water, rocky ground and glaciers. The most obvious question remains: why?

“I was coming up to the end of my contract playing rugby for Hong Kong and was in Kenya playing a tournament,” Rolston said. “My friend Ron had previously done an incredible challenge where he cycled through every country in Africa, before arriving at the South Africa v Japan game in the 2015 World Cup. He was asked to do a talk in Kenya about this challenge and it got me thinking – could we do something together?”

Rolston takes some tips from his caddie. Photograph: Andrew King

Rutland and Rolston had both finished their rugby careers, and sat down at home in Hong Kong to think about what they could do next. They decided to try to break the world record for the longest hole in golf and chose Mongolia due to its wide expanses and nomadic heritage. Eight months later, after assiduous planning, they arrived in Mongolia, ready to tee off in aid of the Laureus Sport for Good and the South African Golf Development Board. If they were going to conquer this arduous hole, the two men wanted to raise money for causes they believe in.

Arriving at the first tee at the base of Khüiten Peak was not without difficulties. “We were in a rickety jeep for hours, then put our cart – with all of our equipment – on to a camel. Then had to get on horses until we reached basecamp,” Rolston explains.

Rolston chips in with the heavy lifting. Photograph: Andrew King

“In my mind I was going to arrive at this stunning location with the sun shining, surrounded by glaciers to start the journey. In reality, we didn’t see the sun for four days and we were moving through freezing water pulling our equipment. In that first week, I was sometimes lying awake thinking: how are we going to complete this. Doubts crept in.”

Rutland and Rolston had built a strong bond through their rugby careers and their resolve was tested in the harsh Gobi desert. Rolson is a gifted scratch golfer but playing for kilometres through sand and jutting rocks forced him to adapt.

Adam Rolston makes the most of the cooler evening temperatures. Photograph: Andrew King

Beyond negotiating the difficult and relentless terrain, the two men were starting to face extreme physical difficulties. Rolston went through days of neck and back spasms, while his caddie suffered with a constantly inflamed hip dragging their cart through uncompromising surface. A chance encounter with a wild Mongolian dog they named UB helped to provide the perfect companion for the remaining 1,500km and lifted their spirits when they needed it most. Rolston said they couldn’t have asked for a better secondary caddie.

“We were followed by this beautiful wild dog, who stayed by our side and slept by our tents. This breed of dog is renowned in Mongolia as operating alone and at times fighting with wolves and coming off better than them, so we should have been apprehensive, but it became an incredible part of the trip. This dog was so loyal and protective to us throughout the trip. It really symbolised the nomadic spirit of this beautiful country and we were delighted to eventually leave him with a loving couple in Terelj national park.”

For weeks, as Rolston and Rutland stumbled slowly across Mongolia one shot at a time, they visualised the finish line in Ulaanbaatar. Dragging their by now battered clubs and cart, the pair were joined by friends as they made their way to their final destination in traditional Mongolian clothing. It has been said golf is a good walk spoiled but it helped Rolston and Rutland connect with a stunning country and do something many considered impossible.

Adam Rolston opts for an iron from the rough. Photograph: Andrew King

• This article is from Behind the Lines

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