Teenager Matthew Haycock, armed with a two-foot long machete, was the oldest of the four-strong group who beat Ben Hawkins near the Wednesfield Way bridge at 2am on March 17, Wolverhampton Crown Court heard.
Three of the gang walked past him but the fourth paused to ask him his postcode before the others followed and then surrounded him.
Haycock, aged 19, showed the machete to the victim before taking his phone and punching him in the face, said Mr Bernard Linnemann, prosecuting.
Mr Hawkins was dragged to the ground, hit and stamped on by the gang, continued the lawyer.
The victim was pinned to the ground and warned he would be stabbed if he resisted as his pockets were searched and £30 was taken from his wallet. The group started to walk away but Haycock ran back moments later to return the stolen phone. He also pulled out the machete, said ‘I could have used this’, and reminded Haycock not to report what had happened, said Mr Linnemann.
The group laughed and joked as they left the injured man.
The victim, who was battered and bruised but not seriously hurt, went to the nearby home of his brother and police were alerted.
His attackers went to a nearby McDonald’s restaurant and paid for their food with blood-stained money taken during the robbery. They were arrested soon afterwards.
Mr Lewis Berry, defending Haylock, of Moathouse Lane East, Wednesfield, who had been convicted of possession of a machete five months before the incident, observed: “He had the good sense to return the mobile phone.”
The defendant pleaded guilty to robbery and possession of an offensive weapon. He received four years detention in a Young Offenders Institution. Two other members of the gang, aged 16 and 17, have been dealt with by a youth court while the fourth is still awaiting sentence.
Judge Simon Ward told Haylock: “You were obviously out looking for trouble and I am not naive enough to think there was no significance in you being interested in his post code.”