Goal.com reported that the Italian international has suffered a knee ligament injury which will keep him out for around a month, meaning he misses games against Bologna, Sassuolo and Atalanta in the league before the winter break.
Pirlo will also miss Juve's final Champions League group stage game against Galatasaray, so how can the team cope in his absence, and who will be asked to step up?
Juve's Chase on Two Fronts
Following their late 1-0 win over Udinese—the game in which Pirlo was injured early on—Juventus are three points clear at the top of Serie A after 14 games. Only Inter Milan have scored more than Juve, while only AS Roma have conceded fewer goals.
All in all, Antonio Conte's side are well placed to lead a big charge for the Scudetto this season if they maintain their impressive start.
Elsewhere, Juventus' final Champions League group stage game is a vital fixture at Galatasaray.
Having won just one of their five games so far, Juve simply must avoid defeat against the Turkish side, who will leapfrog them into second with a victory. A draw would see Juve finish on seven points, which Kobenhavn could equal if they beat Real Madrid, but Juve's superior head-to-head record would still see them through.
The absence of Pirlo for that game in particular, then, will be a big blow for the Serie A side.
Pirlo's Impact This Season
The veteran midfielder has been his usual influential self for much of the campaign, setting the tempo for Juventus' game from his deep role and providing the platform for the more energetic and goal-oriented players to have an impact.
Pirlo registers a 90 percent pass success rate and 1.9 key passes per game in the league—of his teammates, only Carlos Tevez surpasses the latter.
He has featured in every league game but one so far, starting 12 times, playing a prominent role in Conte's usual 3-5-2 system.
Pogba, Take Centre Stage
While the league fixtures should not present too much of a problem for Juve without Pirlo, the Champions League is another matter.
Of course, with the very top of the table fairly tight—third-place Napoli will be six points behind Juve if they win on Monday—even one slip-up could see Juventus lose their first-place status before the winter break.
All three of the games they play before then are against bottom-half teams, though Sassuolo in particular have shown exceptional form since their drubbing at the hands of Inter a couple of months ago.
While Conte often likes to switch his midfield players around, he does have four central players who feature more often than not. Without Pirlo now, it will likely be the trio of Arturo Vidal, Claudio Marchisio and Paul Pogba who play the next four games—assuming Conte does not alter the team shape.
Vidal's nonstop energy and final-third threat means he will still be a key performer, but the standout candidate who can make the difference could well be Pogba.
The French midfielder has already shown exceptional form this season and, without Pirlo's passing range from deep to open up defences, can be just as effective with his surging runs from deep and impressive physicality. Not to suggest he's not skilled on the ball, of course, but Pogba's talents in breaking the lines can be a real game-changer which can win important points for his team.
Pogba's ability to sit deep in midfield and break up play will also be especially important against Galatasaray.
Juve will likely operate with a safety-first approach, opting not to concede above all else, where Pogba's awareness and ability to make challenges will be of paramount importance.
Pirlo's absence will certainly be felt, but with Pogba in top form, it doesn't have to be a telling absence over the next four games.