The 31-year-old, who won gold in both the 5000m and 10,000m at London 2012, is untested and unproven over 26.2 miles and will be racing against four of the 10 fastest marathon runners in history.
Farah, however, has his sights firmly set on Steve Jones' British record of 2hr 7min 13sec, which has stood since 1985.
"Hopefully, I can the break the British record and then we'll see what comes with it," said Farah. "It's going to be an incredible race whatever happens, because if you look at the field, it's something very special.
"The distance is a challenge and that's what I wanted, I wanted to test myself. I'll go with the group and try to be patient - that's my aim, not to waste too much energy."
Doubts over whether Farah can stay the gruelling distance intensified after his performance at the New York City half-marathon last month. He fell early on in the race and while he recovered to finish second behind Geoffrey Mutai, he collapsed shortly after crossing the finish line and had to be pushed away in a wheelchair.
"The reason I collapsed afterwards was I gave 110%," explained Farah. "I gave all I could and towards the last four miles I was really feeling it. I was seeing stars and I was out of it completely."
Farah continued: "It has happened before, when I ran cross country in 2009, so I wasn't worried.
"I didn't really miss any training, the fall was more worrying for me than what happened afterwards, but fortunately I just had a few scratches on my hip and my back."
Also gunning for victory on Sunday will be reigning champion Tsegaye Kebede, world record-holder Wilson Kipsang, course record-holder Emmanuel Mutai, as well as Olympic and world champion Stephen Kiprotich.
Farah certainly has the pedigree on the track to match his rivals, but given he is a novice on the road, it was put to him that he might be risking his reputation in London.
"Every race is a risk," Farah said. "I've gone in straight at the deep end and that's what champions do."