Four-time Olympic champion Mo Farah says winning the London Marathon would be one of his biggest achievements.
The 36-year-old, who retired from track running to concentrate on road races full time in 2017, finished third at last year’s event.
Farah heads into the race in good form, having won the Chicago Marathon in October, breaking the European record.
“I don’t go out to try and finish third or fourth,” Farah said. “I believe I can win more major marathons.”
Farah, who won six world titles on the track, finished in a time of two hours six minutes 21 seconds at London last year and improved that to 2:05:11 in Chicago.
However, he faces defending champion Kenya’s Eliud Kipchoge on Sunday, who set the world record of 2:01:29 at Berlin in September and is going for a men’s record fourth win in London.
Farah, who won gold in the 5,000m and 10,000m at both the Rio and London Olympics, said: “My aim is to win the London Marathon one day.
“That is my task, but you can’t take it for granted because Eliud is a great athlete and a world record holder. If I do beat him it would be an amazing achievement.
“Sometimes you are beaten by a better man and you have to accept that and you go home and think about what you need to do to beat him.
“The rivalry is great for the sport – it’s one the sport needs.”
Farah came agonisingly close to causing an upset in the 2018 race, but he was unable to keep pace in the final stages with winner Kipchoge and runner-up Tola Shura Kitata in what was the hottest race in the event’s 38-year history.