Italy's striking options had been a topic of debate in the build-up to their Euro 2016 qualifying clash against Azerbaijan, with Mario Balotelli missing out on a call-up for the Group H encounter.
However, it was Juventus defender Chiellini who will make the headlines for both positive and negative reasons, having initially opened the scoring for Antonio Conte's men late in the first half when he headed in Andrea Pirlo's corner.
The 30-year-old was then left red-faced when he mistakenly bundled the ball into his own net from a corner with 13 minutes remaining - the first goal conceded by Italy since Conte assumed the reins from former coach Cesare Prandelli.
But Chiellini made amends with what proved to be the winner as he sent a powerful header beyond Kamran Agayev with eight minutes left to play.
It capped off an eventful evening, both for Chiellini and Italy, but maintained Conte's winning start to life with the national side.
Elsewhere in Group H, Nikolay Bodurov scored an own goal in a 1-0 win for Croatia in Bulgaria as Darijo Srna's men kept pace with Italy, while Norway were 3-0 winners in Malta.
In Group A, Netherlands had to come from behind to beat 10-man Kazakhstan 3-1 and get their qualifying campaign back on track, having lost their opener 2-1 to the Czech Republic last month.
Renat Abdulin gave the visitors an unexpected lead 17 minutes into the clash at the Amsterdam Arena and it took Guus Hiddink's men until the 62nd minute to find an equaliser through Klaas-Jan Huntelaar.
Baurzhan Dzholchiev saw red for a reckless challenge from behind on Ibrahim Afellay soon after, before the Olympiacos attacker gave the hosts the lead with a low shot from outside the box in the 82nd minute.
Robin van Persie completed the scoring in the closing stages from the penalty spot after being brought down by Dmitri Shomko.
The Czech Republic's 2-1 win in Turkey sees them remain three points clear of the Dutch, while Iceland are also one win ahead of Hiddink's men after scoring three second-half goals to beat 10-man Latvia 3-0.
Belgium got their Group B qualifiers off to a stunning start as they hammered Andorra 6-0 - Kevin De Bruyne and Dries Mertens both netting doubles.
Israel also made a winning start as they won 2-1 in Cyprus, but Wales now top the group with four points from two matches following a goalless draw at home to Bosnia-Herzegovina.
