A first-half penalty from Daniele De Rossi pushed Italy closer to the Euro 2016 finals on Sunday after a 1-0 in Palermo sent them top of qualifying Group H ahead of Norway.

Three days after a patchy 1-0 win over Malta thanks to Graziano Pelle's winner -- which came off the Southampton striker's arm -- Italy had hoped that a second consecutive win would seal their ticket to next summer's finals in France.

But continuing uncertainty surrounding Croatia, who could be docked one point amid ongoing disciplinary proceedings, combined with Norway's surprise 2-0 win over Croatia in Oslo means Italy now require a point from their final two qualifiers.

Italy now sit two points ahead of Norway and three ahead of Croatia with two qualifiers -- away to Azerbaijan and at home to Norway -- remaining.

On Saturday Italy coach Antonio Conte had expressed surprise over criticism of Andrea Pirlo's performance in the Azzurri's 1-0 win over Malta.

Yet the former Juventus handler bowed to the consensus when he left the New York City FC midfielder on the bench in favour of Roma midfielder De Rossi, a choice that was to bring joy and despair and equal measure.

Conte made further changes, with Antonio Candreva -- who provided the cross for Pelle's winner in Florence -- coming off the bench to start in place of Manolo Gabbiadini and Monaco forward Stephan El Shaarawy taking Eder's slot on the left of Conte's 4-3-3.

Italy got off to a bright start, the hosts pouncing on sloppy defending after just a few seconds to see El Shaarawy come close with a bicycle kick that flew just over after Pelle had forced a save from Bozhidar Mitrev.

Three minutes later, Russian referee Sergei Karasev pointed to the spot after Veselin Minev upended Candreva in the area and De Rossi converted at the second attempt, beating Mitrev inside his left-hand post, after Karasev ruled an encroachment on his first attempt.

On what was Gianluigi Buffon's 150th appearance for Italy, the Juventus 'keeper had comparatively little to do but pulled off a fine one-handed save to touch Ilian Mitsanski's drive around his far post after Bulgaria went on the counter.

Italy, however, dominated throughout and before the interval should have added to their early goal.

Pelle headed over from a Marco Verratti free kick and, after Mattia De Sciglio had forced Mitrev into action following good work by Candreva and Matteo Darmian, the Southampton man saw a volley fly off target.

Candreva wasted a great chance in front of goal, and on the stroke of half-time Parolo saw his volley charged down after being set up by Pelle and Verratti

Both sides were reduced to 10 men 10 minutes after the restart, De Rossi going from hero to villain after retaliating to a foul by Iliyan Mitsanski by kicking the striker while lying on the ground.

Their early exits failed to dampen what was a lively encounter, the excellent Candreva setting up El Shaarawy on the hour mark with a fine angled pass to the back post although Mitrev was quickly out to close down the move.

Bulgaria showed some signs of a fightback, but they were not enough to stop an Italy win that has effectively ended any hope they still had of qualifying for the tournament.