A daunting task awaits John Mousinho and his Pompey side as Premier League leaders Arsenal make the trip to Fratton Park.
The Gunners, who are the highest seed in the competition, visit PO4 for the first time in six years to face the Blues who are in the midst of an injury crisis.
Mousinho’s side, meanwhile, welcome Mikel Arteta’s side off the back of a 5-0 defeat to Bristol City on New Year’s Day after their game against Ipswich Town last week was postponed.
We’ve taken a look at the early team and injury news from both camps ahead of Sunday’s third-round tie.
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13. Florian Bianchini - Out
Bianchini has missed Pompey’s past six matches with a knee injury, with Mousinho confirming the winger is suffering from tendonitis. The Swansea City man is also expected to remain on the south coast for the remainder of the season. | Paul Phelan/ProSportsImages
14. Colby Bishop - Doubt
Bishop is expected to join Pack back in the squad after missing the Blues’ previous two matches due to an unspecified injury. Photo: Getty Images
15. Cristhian Mosquera - Out
The £13m summer signing has been out of action since the beginning of December with an ankle injury, which Mikel Arteta admitted was complicated. | Getty Images
16. Josh Knight - Out
Knight has been sidelined since late November with initial back bruising. Mousinho has since revealed the centre-back is suffering with a stress fracture in the back, which is set to keep him out for at least 4-6 weeks. Photo: Graham Hunt