|2017 Virgin Money London Marathon - Sunday, 23 April|
|Start times: 08:55 BST - Elite wheelchair races, 09:00 - other elite Para races, 09:15 - elite women, 10:00 - elite men and mass races|
|Watch: Live on Eyes On Events Two and Eyes On Events One with extra coverage of the elite races and the finish line on Red Button, online, Connected TVs and app|
|Listen: Live on Eyes On Events Radio 5 live sports extra and Eyes On Events London|
Drugs cheats like 2016 London marathon champion Jemima Sumgong are "ruining the sport", says British five-time Olympian Jo Pavey.
Olympic gold medallist Sumgong, 32, tested positive for banned substance EPO in an out-of-competition test.
Pavey, 43, will race her first marathon in six years on Sunday as she looks to secure qualification for August's World Championships in London.
Six-time Paralympic champion David Weir says Sunday's race "could be" his last.
The women's elite line-up also includes Kenyan Florence Kiplagat, who won last year's Chicago Marathon, compatriot and Tokyo Marathon champion Helah Kiprop, and Olympic 5,000m champion and fellow Kenyan Vivian Cheruiyot, who will make her marathon debut aged 33.
Alongside Pavey, fellow Brits Alyson Dixon, Louise Damen, Charlotte Purdue and Susan Partridge will also compete for World Championship qualification.
'There are still people cheating the system'
Looking ahead to this weekend's race, European 10,000m champion Pavey told Eyes On Events Sport: "It is a shame you have got a winner like Sumgong testing positive because they are just ruining the sport. We're glad that she's been caught, that's one good thing to say.
"You want to believe in a good performance, you want to be looking at athletes winning Olympics and big events and admire their performance.
"There is still a lot more work to do to make sure others are going through the same anti-doping methods as we are in the UK - I had people on my doorstep a couple of days ago and that is what you want to see around the world.
"People like her are ruining the sport because every time you see a good performance, you're wondering is that for real or not."
'I am not getting slower'
Britain's Weir, 37, will be competing in the race for the 18th year in a row, on the back of winning the Paris Marathon men's wheelchair race earlier in April in one hour 29 minutes, 25 seconds.
He told Eyes On Events Sport: "I am just happy to be in good shape to compete. I don't put that pressure on my shoulders [to get the seventh title].
"I wait until the morning to see how I feel - I am in pretty good shape and I am happy with my performance over the past couple of weeks.
"I feel I am not getting any slower - to do that time on that course in Paris, a very rough, hard course. It just gave me a lot of confidence to perform mentally and physically in London.
Asked if it will be his last race, Weir replied: "It could be. But I have enjoyed the training and enjoyed just concentrating on the road, not thinking about being back on the track after the marathon."
In January, the six-time Paralympic champion said he will never wear a Great Britain vest again after an unsuccessful Paralympic Games in Rio last year.
Bekele ahead of the restWhether you're watching or running the London Marathon, it's good conditions for Sunday.
Ethiopian great Kenenisa Bekele, who won last year's Berlin Marathon in the second-quickest time ever, heads the men's elite field along with Kenya's Stanley Biwott.
"Times are very important," Bekele said. "On the track I don't see anyone out there looking like they can reach my marks at the moment. In the marathon, running two hours, 10 minutes and winning would not give you full happiness. Winning in two hours, four minutes would be a different feeling.
"But it is really challenging. It is almost 10,000 metres pace so it is difficult. I had to learn how to run differently from the track, a different foot strike. Every race, every course is different and I am learning with every one."