Leeds United's FA Cup campaign is set to put them at a disadvantage in their promotion bid as they prepare to face Millwall in the cup competition.

Daniel Farke's side earned a hard-fought victory over Harrogate Town in the third round of the competition to set up a fiery fixture against the London club. But Leeds, whose sole FA Cup triumph came in 71/72, are at risk of losing ground to their Championship title rivals who have already been knocked out of the competition.

Both Sheffield United and Sunderland have set their sights on promotion this season and are currently in the midst of the battle to ascend to the Premier League. The clubs currently sit in third and fourth positions, two and three points off table-topping United respectively.

Both clubs are in league action on February 8 when the Whites host fellow second-tier Millwall in a match that United are expected to win and advance to the FA Cup fifth round.

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Meanwhile, Sunderland welcome promotion-chasing Watford to the Stadium of Light while Sheffield United play a struggling Portsmouth, also at home, on the same day as Leeds' FA Cup clash.

If both teams were to win their fixtures, Sheffield United would leapfrog Farke's side to move two points clear of them while Sunderland would move level on points, with 53. The FA Cup fixture gives Leeds the opportunity to avenge November's 1-0 loss to Millwall, at The Den, which saw defender Junior Firpo retrospectively handed a three-match ban by the FA for an apparent headbutt.

The left-back returned to action in the the 1-0 win against Harrogate following a hamstring injury which has kept him out since early December. Sunderland were bested at home by Stoke City, 1-0, in the last round of the cup while Sheffield United also lost at home to Cardiff City.

Elsewhere, Championship chasers Burnley have a trip to Southampton in the fourth round.