Rome, February 13 - Juventus said they have sent out a signal to themselves and to Europe's big guns by closing in on qualification for the Champions League quarter-finals with Tuesday's 3-0 over Celtic in Glasgow. The scoreline of the first leg of the last-16 tie suggests the Turin side made light work of the Scottish champions, but the Serie A title-holders actually spent long spells defending. They managed to keep their composure in the Parkhead cauldron, hit on the break and capitalised on some defensive errors to prevail with goals by Alessandro Matri, Claudio Marchisio and Mirko Vucinic. "It was a fantastic team performance and a key win," said Marchisio. "We're not through yet but taking a 3-0 lead back to Italy means we can concentrate a bit more on the Italian league. "We've sent out a message tonight, to ourselves more than anything. If we maintain our focus as we did today and in our last two Serie A games, we can go on to achieve great things. "It's no mean feat to come here and win in Glasgow, but we studied our opponents well and we got our approach spot on. "We wanted at least one goal... and we managed to score three". Italy goalkeeper Gianluigi Buffon said Juve, who are five points clear at the top of Serie A, had done well to get the most out of a tough match. "Celtic are an excellent side and they showed that tonight," Buffon said. "We set out to attack them but struggled to get into our rhythm so we had to settle for what we could manage, which was to defend well and break forward on the counter. "We did a great job of it too - we were clinical and ruthless. "We have to be honest though - the game hinged on a couple of decisive moments. If you didn't watch it, you might think we cruised to victory. "But it's a positive sign that things went our way and also that we took our chances".