Allyson Felix will seek to maintain her perfect record in Doha in Friday’s first IAAF Diamond League event of 2013. But gaining her 11th victory in Qatar since 2005 will be a steep task indeed for the 27-year-old US sprinter given that she is racing over 400m, which by her own admission is not her specialist distance, against a field which includes the reigning World champion and defending Diamond Race winner, Amantle Montsho of Botswana.