Massimiliano Allegri insists AC Milan will shelve all thoughts of next week's clash at Barcelona until after Friday evening's Serie A opener against Lazio.Milan will get their UEFA Champions League campaign underway in style when they travel to Camp Nou next Tuesday to take on the holders in Group H.But before that game the Rossoneri must host Lazio in the league at San Siro, with Allegri under no illusions over the importance of the curtain-raiser for the Italian champions."We must only think of tomorrow's home game," said Allegri. "From Saturday onwards we will think of Barcelona."The Lazio game will be really difficult. Firstly, because it's the first game and then because we have not played in quite a long time."The difficult thing will be to have the right mental approach. Lazio are a team who will battle for the title. They are strong and, like us, they are playing together this year."This game with Lazio is the most important game of those we will play from now until December."Allegri also says Milan are determined to build on their league success from last term.He added: "My team have more motivations than last season."The guys want to show that everything we did last year is down to a big job, big will and big will to grow." From / BBC