By Julien Pretot FLORENCE, Italy (Reuters) - Portuguese Rui Costa kept his composure in a tense finale to upset the favorites and win the cycling world championships road race following a series of crashes and persistent rain on Sunday. After sitting behind and refusing to take turns at the front, Costa made his move some 1.5 kms from the finish to bridge the gap with Joaquim Rodriguez and beat the Spaniard in a sprint finish to become the first Portuguese to win the event. ... More...