The Czech insists that if the Blues perform to their best they can handle the brilliant Argentine and believes the reigning European champions are not \"invincible\" Chelsea goalkeeper Petr Cech is confident the Blues can stifle the threat of Lionel Messi ahead of their Champions League semi-final first leg with Barcelona at Stamford Bridge.The Argentine forward has been in scintillating form this season, notching over 60 goals in all competitions, including 14 in Europe’s premier club competitionCech says Chelsea are well aware of the threat the 24-year-old will pose their defence, but believes they can defend against him.“[Lionel] Messi in his current form is an enormous threat,” Cech told his personal website.“He is for sure one of the best players in the world but, as I said before, no team is invincible.“His ball technique is superb but, most importantly, he can react to how the game develops. At the last possible moment in any situation he can find the ideal solution. There are a lot of ways that Messi can finish an attack.“On the other hand, he is also only human and, if we perform to 100%, we will be able to defend against him.\'Cech also concedes that Chelsea are underdogs going into the game, but believes it is not above the Blues to pull off an upset.“They [Barcelona] are the biggest favourites of the Champions League, they are defending the trophy but anything can happen,\" he added.“We have two matches in which we can overturn the prognosis about favourites.”