Balotelli has not played for Italy since their first-round exit from the World Cup in Brazil and until his call-up on Sunday was left on the sidelines by new Italy coach Antonio Conte for their first three Group H qualifiers.

The 24-year-old striker is no stranger to controversy, having spent two and a half well-documented years in the English Premier League with Manchester City, where he missed 11 domestic games after taking the club to a tribunal following their decision to fine him two weeks' wages for his poor disciplinary record.

After returning to Italy in January 2013 for an ill-fated 18-month spell with AC Milan, Balotelli signed for Liverpool in the summer but has been pilloried since having failed to spark and, worse, failed to score in the league.

Conte's decision has left more than a few observers scratching their heads in wonder.

"Balotelli was only called up by Italy because of the injury suffered by Lorenzo Insigne," claimed Francesco De Luca, chief editor of Il Mattino newspaper, on the football talk show Il Processo di Lunedi.

Another guest on the show, former Inter player Evaristo Beccalossi, gave an equally unflattering appraisal of Balotelli, who played for the Nerazzurri before his move to City.

"We've always said that Mario's presence should depend on how he is playing, but it's evident that at Liverpool he's not performing well," said Beccalossi.

"He's found it difficult from the start there, but Conte has selected him. In the coach's defence, you have to say the strikers we have are not all top notch."

Whether on or off the field, Balotelli has courted controversy at almost every club he has played.

Reports from England on Tuesday said Balotelli was seen out partying at a London nightclub until 4:30a.m. following Liverpool's 2-1 defeat to Chelsea, a game in which Balotelli was conspicuously under par.

Several weeks ago he was pilloried by fans and the unforgiving British tabloids after he swapped shirts with Real Madrid player Pepe as they walked off at half-time. Liverpool lost 3-0 and Balotelli was replaced at half-time.

While Liverpool manager Brendan Rodgers said he would "deal with the incident internally", former Reds great Jamie Carragher hit out: "I'd be surprised to see him here next season if I'm being honest."

Asked by Rai Sport on Monday for his opinion on Balotelli, former Ajax and Barcelona hero Johan Cruyff said: "It's a problem of education, if he had been educated well he would not be like he is now."

Few commentators got behind Balotelli, although in Tuttomercatoweb.com former Milan and Rangers striker Mark Hateley called for Liverpool fans to show patience.

"Conte was right to call him up because at international level you get the best out of Balotelli," said Hateley.

"Mario is suffering from the fact he is being compared to Luis Suarez and I think that's wrong. Suarez scored a lot of goals and was driving force behind Liverpool and you can't replace a guy like that.

"Of course, he (Balotelli) isn't scoring, he's not playing well. But Liverpool are not playing well and it's not easy for Balotelli.

"He's lacking confidence and maybe this call-up will be the spark that gets him going again."

Conte, meanwhile, said he has not taken Balotelli's Liverpool woes into consideration.

"Personally, I don't pay attention to what's being said about his club situation," Conte said on Monday when the Italy squad congregated at their Coverciano training base near Florence.

"Today he's here and he has to answer to me. I will judge him by what he does in the next seven to nine days."

Italy sit second in Group H behind Croatia on goal difference after winning their three opening qualifiers. They host the Croats at Milan's San Siro ground on Sunday.