Milan, August 20 (IANS): Six-time defending champions Juventus and title contenders Napoli posted easy victories over Cagliari and Hellas Verona on the first day of the Serie A football season. In Turin, Argentine strikers Paulo Dybala and Gonzalo Higuain each scored goals on Saturday to lead hosts Juventus to a 3-0 victory over Cagliari, reports Efe. After losing the Italian Super Cup against Lazio on August 13, the record defending Serie A champions successfully kicked off the new league season at the Allianz Stadium. Croatian striker Mario Mandzukic opened the scoring after just 12 minutes with a half-volley following a cross from right-back Stephan Lichtsteiner. Cagliari failed to equalise after veteran goalkeeper Gianluigi Buffon saved a penalty in the 39th minute. Young defender Daniele Rugani stepped up for Juventus, who sold ace centre-back Leonardo Bonucci to AC Milan. Rugani partnered veteran Giorgio Chiellini at the heart of the home defence. Dybala then scored the second goal for Juventus during stoppage time of the first half following a long-range ball from Miralem Pjanic. The Turin club got another insurance goal when Higuain scored in the 66th minute with a left-footed finish from close range. Juventus also handed Serie A debuts to new signings, winger Douglas Costa (from Bayern Munich) and midfielder Blaise Matuidi (Paris Saint-Germain) -- both coming on as substitutes. "It's good that we've got off on the right foot. I'd seen lots of good signs before today but when you win matches it helps you train in the right frame of mind. We got our approach spot on today," Juventus head coach Massimiliano Allegri told his club's website. In the other match of the day, visiting Napoli side went ahead 2-0 in the first half, thanks to an own goal from Samuel Souprayen and a strike from Poland striker Arkadiusz Milik. Faouzi Ghoulam's marked his 100th appearance for Napoli with his maiden goal for the club in the second half. Giampaolo Pazzini pulled one back for the hosts with a penalty conversion.