Two college students robbed a teenager at knifepoint in daylight.
The 18-year-old victim was walking along The Newarke when he was accosted by the pair, who were wearing hoods and scarves.
One – Joseph Makande (18) – grabbed the victim, putting his hand across his chest.
He shoved him against railings, saying: "What have you got?"
Makande's 17-year-old accomplice blocked the victim's path and attempted to search his pockets, demanding his mobile phone.
When he resisted, Makande threatened: "Let us have your phone or I'll stab you."
The victim felt a sharp point in the lower left side of his back and looked down to see a knife with a four-inch blade.
Leicester Crown Court heard that passers-by appeared too frightened to respond to pleas for help.
The 17-year-old juvenile took the victim's phone.
The incident left the victim traumatised and suffering from panic attacks and nightmares, the court heard.
He was too frightened to walk to work afterwards and had the expense of taking taxis and moving closer to work.
He feared the robbers would strike again and, because he did not see their faces, felt scared when he saw males of a generally similar appearance.
CCTV cameras captured the defendants afterwards changing their clothes.
Judge Ebraham Mooncey said: "This is an example of a case where CCTV footage assisted greatly."
He said footage showed them appearing to "swagger" away looking pleased, before they were arrested.
Makande, of Tomlin Road, Northfields, Leicester, admitted robbery and possessing a knife during the incident, which happened at 5.50pm on June 15.
He received 16 months' detention.
The juvenile, also from Leicester, cannot be named because of a court order.
He was given a two-year youth rehabilitation order, with 12 months' supervision, and 180 hours of unpaid work.
He was also ordered to pay £700 compensation to the victim and £500 costs, the responsibility for which falls to his parents.
He admitted robbery on the basis he had no advance knowledge Makande was going to produce a knife.
In mitigation, the court heard the defendants were both college students, from respectable homes.
Their parents disapproved of their actions.
Justine Robinson, for Makande, said: "He is remorseful and understands the effect upon the complainant."