McKiernan, whose winning time of 2hr 23min 44sec in Berlin has been bettered by only seven athletes, appears to have an excellent chance of adding another victory over 26.2 miles closer to home.
If she does, it will come as no surprise to the sports physiologists at Trinity College, Dublin who have monitored her aerobic performance regularly over the last nine years.
"They have always told me I had a marathon runner's make-up," the 27- year-old Irishwoman said yesterday. "They have been nagging at me to run a marathon for years, but I have erred on the side of caution because I didn't want to do too much too early in my career."
Not that McKiernan has been marking time up to now - she has established a huge reputation in cross-country, winning the inaugural European title and, tantalisingly, taking silver at the World Championships four times.
The lure of trying to add a world gold is still there - she will run in the cross-country event at Durham in January as part of her preparations, and has not ruled out competing at the next World Championships in Morocco.
The fact that that race will be held over 10 kilometres, rather than 6.5 as it has in recent years, will favour a runner who has always looked comfortable at the longer distances.
McKiernan's marathon credentials will be tested to the full in London, however, following yesterday's confirmation that she will face Liz McColgan, beaten into second place by just one second in the 1997 event, and Hiromi Suzuki, the reigning world champion.
The Irish runner believes Ingrid Kristiansen's world record of 2hr 21min 06sec - set in London in 1985 - may be within her reach.Reuse content