His next major competition came in October 2010 at the Athens Classic Marathon, which was celebrating the 2500th anniversary of the Battle of Marathon. His compatriot Jonathan Kipkorir was the favourite for the race but Bett upset the predictions by going on to win his first ever marathon. He led the race alongside the pacemakers and crossed the line over a minute ahead of the competition to improve Paul Lekuraa's race record to 2:12:40. "It is my first marathon victory and I feel good", he said. "It is a difficult course with a lot of hills and up and downs." He set his sights on returning the following year in order to attempt to beat Stefano Baldini's overall course record set during the 2004 Athens Olympics.