The Foxes, of course, are the defending Premier League champions, but Claudio Ranieri's men have fallen well short of the standards set last season in domestic competition thus far this term.
Steve McClaren's charges have already beaten Premier League opposition in this competition this season, knocking out West Bromwich Albion in the previous round, and the Rams would dearly love to take another significant scalp when they renew their rivalry with Leicester.
Derby have won six of their last seven matches on home soil and can be backed at 8/5 (2.60) with Betfair Sportsbook to send Ranieri's men crashing out of the competition, while the same firm go 2/1 (3.0) that a replay is required to separate the sides.
Leicester came from behind at Goodison Park to knock Everton out of the competition in the previous round, but that was their only win in 12 matches on the road in all competitions, while they have failed to win a Premier League match on their travels so far this season. Betfair offer 7/4 (2.75) that they come out on top and reach the fifth round for the second time in three seasons.
Derby's defensive discipline could hold the key for McClaren's men. They have kept a clean sheet in eight of their last nine home games and Betfair Sportsbook offer a tempting 2/1 (3.0) that the Championship side keep another against Leicester.
Ranieri’s men have scored just three goals in their last six matches in all competitions and, having suffered back-to-back 3-0 defeats against Chelsea and Southampton respectively, the 65-year-old Italian will be acutely aware of the importance of an improved performance from his side if they are to avoid falling victim to an FA Cup shock.
Both of Derby’s most recent Cup defeats have come against top-flight opposition, with Manchester United eliminating them from the FA Cup last term, while Liverpool romped to a 3-0 win when they visited iPro Stadium in the EFL Cup back in September.
Beating West Brom in the third round, though, will give the hosts reason to be optimistic and, in truth, Leicester look to be a shadow of the side that secured that stunning title triumph last season; as such, they are certainly vulnerable ahead of the short trip.
Derby are unbeaten in nine matches on home soil and are superb value at 8/5 (2.60) to claim a famous win on Friday night.