While Watford sit in fourth place in the Championship and Reading occupy 13th spot, just four points separate these sides in what is a very competitive division.
Watford managed to take all three points with a 2-0 home win back in early November, and Reading will hope to exact revenge in this cup tie.
Watford boss Slaven Bilic is facing a serious injury crisis at the moment, which worsened last weekend, when on-loan Aston Villa forward Keinan Davis and first-choice centre-back Christian Kabasele both picked up muscle injuries, which forced them to leave the pitch early.
Winger Samuel Kalu also came off carrying a knock, whilst goalkeeper Daniel Bachmann appeared to injure himself in a clash with the advertising hoardings.
Joao Pedro is notably the most influential player on the long-term injury list, while Hassane Kamara is still suspended following his red card against Millwall on Boxing Day.
Reading, on the other hand, do not have many personnel issues, and the team that many tipped to be relegated this year have been performing admirably under manager Paul Ince.
Indeed, the Royals are still in the hunt for a playoff spot, leading Ince to state following Monday's 1-0 defeat at West Bromwich Albion, that he would 'not fully go for it' with regards to Reading's FA Cup campaign this season.
That said, the Reading boss did promise fans that he would send out a team which is more than capable of winning this tie.
These two clubs met in the league just two months back in early November, when Watford ran out comfortable 2-0 winners at home, thanks to a brace from Brazilian Joao Pedro.
Since then, Watford have been struck by all the injuries, and at least seven of the team that started that fixture will miss out here.
For that match, Watford were heavily opposed within the markets, and having opened at around a price of 4/6, they had drifted out to 10/11 by kick-off time, with late money heavily favouring the Royals.
Sharp punters may again look to oppose Bilic's men, with Watford expected to name a very weak side due to the issues mentioned.
In addition, key players such as Ismaila Sarr may be in line for a rest, having been heavily relied on in recent games.
Conversely, despite Ince promising to shuffle his pack to some extent, home advantage and less rotations than their opponents could lead to Reading being a value play come kick off time, and they currently appear handily priced on the Draw No Bet line.