Barcelona coach Pep Guardiola has admitted that the Blaugrana are unlikely to retain their La Liga crown, but vowed to continue fighting until the end of the campaign.The Catalans met heavy resistance from Atletico Madrid at the Vicente Calderon on Sunday, but managed to edge the game courtesy of a wonderful late strike by Lionel Messi after Dani Alves and Radamel Falcao had scored earlier on."I don't think we will win the league, but we will fight until the end," said Guardiola at the post-match press conference."We have passed a difficult test against a very tough opponent."And the Catalan coach also took time to praise the Argentine for his leadership qualities after the 24-year-old's improvised free-kick gave Barca victory."A leader is he who steps forward when his team needs him and Leo [Messi] has been doing that for four years," he explained.Barcelona are 10 points behind Real Madrid in La Liga, and now face Sporting Gijon next weekend.