London 2012: Marathon 'last chance' for Olympic qualifiers
The London Marathon on Sunday will be one of the last opportunities for athletes to qualify for the Olympic Marathon in August.
Only one man, Scott Overall, has so far qualified for Team GB and he has been named as the official London Marathon pace maker. He ran the Berlin Marathon in two hours 10 minutes and 55 seconds in 2011 to qualify.
He is hoping his efforts will help other British athletes join him on the Olympic start line, as BBC London's Sara Orchard reports.