Kirani James may be the world champion heading into the 400m in London, but experience can be expected to tell and although just odds-on, LaShawn Merritt is the better bet to retain his Olympic gold in the event at 4/6.
James become the youngest ever 400m world champion with his success in Daegu and went from strength to strength in 2011 when going onto a Diamond League meeting in Zurich and setting a new personal best of 44.36 secs.
However, the slight concern is that he has not shown much development in the current season, either in terms of time or his rugged running style.
In fact, breaking 45.00 secs this season has proved a reasonable challenge, let alone setting a new career fastest time.
Merritt may have been outsprinted down the home straight by James in Daegu, but it can certainly be argued that he turned up to the championships without being in optimum race condition.
The American had not long returned from a two-year drugs ban and perhaps found the format of qualification races and a final in a short space of time too much.
This year he has no such excuse and has looked fairly invincible.
Merritt posted the quickest time of the year with a 44.12 secs in the US trials for a 400m spot at the Olympics and has also run a 44.19 secs in Doha.
Meanwhile, he beat James, who is 7/2 to win gold in London, when the pair clashed in Oregon at a Diamond League meet.
The 400m does really look between these two athletes, with another teenager in Luguelin Santos from the Dominican Republic likely to be fighting it out with the US number two Tony McQuay for the bronze.
Santos has run 44.35 secs this season and is 6/1 to take gold, with McQuay available at 10/1 and leading British hope Martyn Rooney a 25/1 shot.
All Odds and Markets are correct as of the date of publishing.