After nearest rivals Inter Milan romped to victory against Genoa earlier in the day, the Bianconeri restored their six-point cushion at the top of the standings with a 3-1 triumph at the Allianz Stadium.
Juventus got off to the dream start as Paulo Dybala struck inside the opening minute, but Cagliari came back into proceedings and leveled superbly though Joao Pedro.
However, Filip Bradaric scored an own goal just 125 seconds later and Juan Cuadrado diffused rising tension late on by sweeping home Cristiano Ronaldo’s cross.
While it was at times an unconvincing display, it acted as a solid warm-up for Wednesday’s Champions League Group H clash with United – a match where anything but defeat will seal the Italian giants’ progress to the last-16.
‘It’s not easy to win 10 out of 11 matches,’ Juventus head coach Allegri said. ‘We got off to a good start but weren’t able to add a second and then we disappeared from the game a little.
‘We must do better defensively in our own half. We take too many things for granted. We assume we’ll score two or three goals every game, but we can’t always do that. We have to be capable of grinding out 1-0 wins too.
‘We need to keep clear heads at all times, otherwise we can concede from the opposition’s first cross and then almost concede another from Cagliari’s only chance in the second half.
‘It’s one of the few things we’re not doing so well, and we must work on it and concentrate more. Now we can focus on Manchester United.
‘We must try to secure our place in the next round on Wednesday and then end this run of matches with a good result at AC Milan before the break.’
Allegri approaches Wednesday’s Champions League match with some questions over key players’ availability.
‘Douglas Costa had a muscle problem, (Miralem) Pjanic was starting to feel a bit tired and (Blaise) Matuidi sustained a knock,’ he said.
‘(Giorgio) Chiellini will be available on Wednesday and (Federico) Bernardeschi should be too. As for (Mario) Mandzukic, we need to take a look at his ankle and assess him.’
United will be boosted by the way Cagliari made life tough for Juventus, with visiting head coach Rolando Maran left feeling hard done by.
‘There is anger and regret,’ he said. ‘We went close to doing the business. We return home without points but certain that we deserved more.’