MILAN: Juventus coach Massimiliano Allegri believes that defending is just as much as an art form as attacking and advises anyone who wants to watch a show to go to the circus. The dominant force in Italian football, Juventus will take on the role of underdogs when they host Barcelona's array of creative talent in the first leg of their Champions League quarter-final on Tuesday. Yet while Barca boast Europe's most spectacular strikeforce, Juve have arguably the continent's best defence, based on the 'BBC' line-up of Andrea Barzagli, Leonardo Bonucci and Giorgio Chiellini, underpinned by veteran goalkeeper Gianluigi Buffon. Juventus, well on course for a sixth successive Italian title, have conceded only two Champions League goals this season and just 20 in 31 Serie A games, making them a tough nut to crack even for Barcelona's prolific trio of Lionel Messi, Luis Suarez and Neymar. Despite this, Allegri has faced criticism that his side have often had to grind out results rather than winning in style, but he reckons such comments make him smile rather than anger him. "Football is very simple and consists of two aspects that you have to do well -- attacking and defending," he said. "There's no shame in being good at defending. In fact, it's just as beautiful as a great attacking move. "I am very happy for those who can turn football into a show but, as far as I'm concerned, if you want to see a show, you should go to the circus. "Committing fouls and winning aerial battles are also very important." He also pondered whether dominating possession -- as Barca do routinely -- was a good thing. "Sometimes, you have 35 percent possession and create seven or eight scoring opportunities. Some games, you have 70 percent possession and have three shots on target. So which is better?" Not that the omens are too promising for Allegri, who has already faced Barcelona nine times, including eight Champions League meetings in three seasons when he was coach of AC Milan, and managed just one win. His Milan side were knocked out 3-1 on aggregate in the 2011-12 quarter-finals, then lost 4-2 on aggregate in the round of 16 the following season despite winning the first leg 2-0 at San Siro. He also faced them as Juventus coach in the 2014-15 final when Barcelona won 3-1 but the phlegmatic coach remains undeterred. "Nothing is impossible," he said. "Above all, we have to play a perfect game on a technical level. We have to play, believing we can go through. We'll need to be at our best both when attacking and defending."