Tola Shura Kitata of Ethiopia stayed with Kipchoge until close to the end but the 2015 and 2016 champion strode clear to win with a time of 2:04:17 - two minutes 20 seconds off the world record.
After reaching halfway in 1:06:54 previous year, Keitany passed through the corresponding point still inside world record pace at 1:07:16.
The men's race went out at a blistering pace, with early leader Guye Adola clocking four minutes 22 seconds in the first mile, and Farah stayed with the group until a freakish incident when he missed his drinks bottle around the 10-mile mark, which delayed him after a heated exchange with a steward.
"I still enjoy the win and I'm happy to be able to win for the third time in London". "I gave it all, 110 percent as I normally do", said Farah. "You don't win medals overnight and I believe it's the same in the marathon". You get heavy legs, mentally you need to be strong and pace yourself. I can't be unhappy with third, looking at the quality of that field you would never have put me there before the race.
The only talk of football on Sunday, however, related to him potentially painting his drinks bottles in Arsenal colours in future so he can pick them out more easily at roadside feeding stations.
Kathua: Students' protests, clashes in Ajas Bandipora
Following the protests, all the educational institutions and business establishments were closed in the Anantnag town for the day. The protestors accused the police of using force at some places to quell protests, a charge denied by the police.
"I was saying to the people on motorbikes to tell the staff to be a bit helpful".
In th Womens' Marathon, Kenyan Vivian Cheruiyot took home the Gold medal.
Kenyan Mary Keitany and Ethiopian Tirunesh Dibaba - who had both hoped to break the 15-year-old record for best women's time - both finished further down the pack.
After nine miles Keitany and main rival Dibaba were 25 seconds ahead of Radcliffe's time.
Her compatriot Kurt Fearnley came fifth in the men's event, following a thrilling three-way dash for first that saw England's David Weir storm to an eighth victory. But not only did he run two minutes quicker in the 2018 race but he ran with no fear as he boldly tagged on to the suicidal early pace (4:22 for the first mile, 13:48 for 5km and 28:19 at 10km - which is sub-two-hour pace - before slowing to a mere 61:00 at halfway) and he mixed it with Eliud Kipchoge, Kenenisa Bekele, Daniel Wanjiru and others.
Weir, 38, pipped Switzerland's Marcel Hug into second place, with Daniel Romanchuk of the US third.