Here’s all the key information you need to know ahead of the tie…
Pompey team news
Denver Hume: Portsmouth's expensive forgotten man and why former Sunderland defender really could be one for the future
'We wanted to show him a bit of love' - Portsmouth-based Spurs fans' terrific gesture to ensure Dane Scarlett feels at home on the south-coast
League One latest: Portsmouth linked duo set for Oxford United and Lincoln moves, Southampton prospect joins Blues rivals as Ipswich land former Blackpool and Derby veteran
'Real driving force... lion-hearted display... classy presence' - Neil Allen's Portsmouth ratings from 3-0 Carabao Cup win at Cardiff
'We’ve got a real problem': Portsmouth boss reveals headache after career first at Cardiff
Pompey are short of forward options ahead of the Hoops’ visit to Fratton Park.
Jamal Lowe is suspended, Louis Dennis is a slight doubt after picking up a knee injury and Oli Hawkins remains sidelined with a calf problem.
To make matters worse, Andy Cannon is cup-tied having featured in the FA Cup for Rochdale this campaign.
And youngsters Dan Smith and Brad Lethbridge have also represented Bognor in the second-qualifying round against Whitstable.
Matt Casey too played for Gosport Borough against Ramsgate in the historic competition.
Nathan Thompson (hamstring) and Luke McGee (wrist) remain on the treatment table.
QPR team news
Steve McClaren will field a strong team at Fratton Park.
The Hoops are without veteran defender Angel Rangel, who is sidelined with a thigh injury.
On-loan Brighton striker Tomer Hemed is also absent until at least the middle of next month after undergoing a hernia operation in December.
United States international Geoff Cameron (ankle) won’t be involved at Fratton Park.
Referee: Gavin Ward (Surrey)
Pompey’s form this season
Top scorer: Jamal Lowe (11)
Most assists: Ronan Curtis (13)
Most games: Matt Clarke (36)
QPR’s form this season
Top scorer: Luke Freeman (6)
Most assists: Nahki Wells (3)
Most games: Luke Freeman (31)
Pompey’s recent form
W 1-0 Peterborough (H) Checkatrade Trophy January 22
L 2-1 Oxford (A) Checkatrade Trophy January 19
L 1-0 Blackpool (H) League One January 12
W 2-0 Southend (A) Checkatrade Trophy January 8
W 1-0 Norwich (A) FA Cup January 5
QPR’s recent form
L 4-1 Preston (H) Championship January 19
L 1-0 Sheffield United (A) Championship January 12
W 2-1 Leeds (H) FA Cup January 6
D 2-2 Aston Villa (A) Championship January 1
D 0-0 Reading (H) Championship December 29
Odds – provided by The Betting Room, Southsea
Other fourth-round fixtures
Today (all 3pm kick-offs unless stated)
Accrington Stanley v Derby County (12.30pm), Brighton & Hove Albion v West Brom, Doncaster Rovers v Oldham Athletic, Manchester City v Burnley, Middlesbrough v Newport County, Newcastle United v Watford, Shrewsbury v Wolves, Swansea City v Gillingham, Millwall v Everton (5.30pm), AFC Wimbledon v West Ham (7.45pm).
Crystal Palace v Tottenham Hotspur (4pm), Chelsea v Sheffield Wednesday (6pm)
Barnet v Brentford (7.45pm)