Lionel Messi says Barcelona are not used to receiving such negative press, following disappointing defeats to AC Milan and Real Madrid in the last fortnight.Speaking about the 3-1 defeat to Madrid at Camp Nou on Tuesday, Messi admitted that the squad are struggling to come to terms with the result, especially as it came so soon after the 2-0 defeat to AC Milan at San Siro a week prior."We are not used to dealing with a situation like the one we are going through at the moment," Messi wrote on his Chinese social media Weibo profile.Despite the negative reaction to Blaugrana's recent performances, Messi says he has no doubt in his mind that both he and his teammates will bounce back and produce a response when they face Madrid at the Santiago Bernabeu on Saturday."I have a lot of faith that this group will keep moving forward," the Argentine added.Messi has been singled out for criticism by some for his subdued performances in both games, but rumours that he was not 100 per cent gathered pace when the Argentine missed training on Wednesday due to a fever.