Born in the San Basilio suburb of Rome, Petrucci began his football career with his local club, Roma, playing in their youth team. During the 2007–08 season, he scored 14 goals in 19 appearances for the Roma youth team, alerting Manchester United to his talents. But the AS Roma offered him a contract worth only around £16,000 per annum, the minimum wage for Italian youth team players, claiming that it would upset the other youth players who had already accepted similar deals if they offered him any more. However, despite the club's claims that he would have been given opportunities in the first team in the 2008–09 season, Petrucci expressed concerns that he had not already been called up. When he asked Roma for some time to consider their offer, the club gave him a three-day deadline. Around this time, Manchester United offered Petrucci a £95,000-a-year contract, which the Italian youngster accepted on 13 June 2008. To comply with FIFA regulations with regard to the international transfer of players under the age of 18, United also offered Petrucci's father, Stefano, a job as well as offering to pay for regular flights back to Italy.
Manchester United
United paid Roma approximately £200,000 in compensation for the transfer, which the Italians were unable to contest as Petrucci was not under contract with them. Italian football regulations state that under-17s may not be signed to professional contracts, meaning that Petrucci would not have been able to sign with Roma until his 17th birthday in October 2008. He travelled to Manchester on 30 June 2008, and began training with Manchester United the following day. At the end of July 2008, Petrucci was part of the Manchester United team that won the Premier section of the 2008 Milk Cup. He made regular appearances for the Manchester United under-18 side during the 2008–09 season, and got his first taste of reserve team action on 18 November 2008, when he played 20 minutes of a 2–1 defeat away to Hull City, coming on as a substitute for Antonio Bryan. On 22 January 2009, he made another appearance for the reserve team in the Manchester Senior Cup, scoring the first of the team's three goals in the fourth minute of a 3–0 win over Accrington Stanley.
On 2 September 2013, Petrucci was initially loaned to Belgian side Royal Antwerp until the end of the season, but was recalled in January 2014. On 27 March 2014, Petrucci joined Championship side Charlton Athletic on loan until the end of the 2013–14 season.
CFR Cluj
On 8 September 2014, after being named in United's 25-man Premier League squad, Petrucci terminated his contract by mutual consent to secure a move to Romanian side CFR Cluj, six days after the transfer window closed.
