Pompey have been drawn away to League Two side Cheltenham in the second round of the Papa John's Trophy.
The tie will be played at Whaddon Road in the week commencing December 7.
Competition holders Pompey – who are still waiting to play Salford in last season's final – were guaranteed an away fixture after finishing second in Southern Group A.
Michael Duff's Robins, meanwhile, topped a group containing Norwich U21s, Plymouth and Newport with a 100 per cent record and without conceding a goal.
They were beaten in the fourth tier play-offs at the end of last season and are currently sitting third in the table.
|Papa John's Trophy Round Two – South|
|AFC Wimbledon v Arsenal U21*|
|Milton Keynes Dons v Norwich City U21|
|Peterborough United v West Ham United U21*|
|Oxford United v Forest Green Rovers|
|Cambridge United v Gillingham|
|Exeter City v Northampton Town|
|Cheltenham Town v POMPEY|
|Leyton Orient v Bristol Rovers|
|Papa John's Trophy Round Two – North|
|Shrewsbury Town v Lincoln City|
|Salford City v Leicester City U21|
|Fleetwood Town v Blackpool|
|Port Vale v Wolverhampton Wanderers U21|
|Hull City v Crewe Alexandra|
|Accrington Stanley v Manchester United U21|
|Tranmere Rovers v Manchester City U21*|
|Oldham Athletic v Sunderland|
*Arsenal, Manchester City and West Ham were all drawn at home, but have been given special dispensation to play any fixtures in the knockout stages of the competition away from home.