While Leicester's downturn has proved cause for concern, the hosts have taken no points from their last four matches to slip down the second-tier standings.
Match preview
Following a miserable end to February - during which Michael Beale's doomed spell in charge was cut short - Sunderland started the new month in similar fashion, as hopes of a precious top-six finish further receded.
Interim head coach Mike Dodds has been unable to turn things around since stepping into the dugout, and the Black Cats' latest defeat came at Carrow Road, where they were edged out by fellow playoff contenders Norwich City.
Sunderland had won on their three previous league visits to Carrow Road but could not find a late leveller after falling behind in the 81st minute, so they sit 10th in the table, some nine points adrift of sixth place.
As ever, there is little time to reflect on events in the action-packed Championship, and Dodds will send his side out at the Stadium of Light on Tuesday evening: a recent 2-1 defeat to Swansea there was Sunderland's seventh home loss in the Championship this term - as many as they suffered throughout all of last season.
The Wearsiders will therefore be keen to give their fans something to cheer about in midweek, and after enduring four straight defeats by single-goal margins, they may be due a change in fortune.
However, not only have Sunderland slipped off the pace before meeting the Championship leaders, but they have also lost four of their last five league games against Leicester City.
Now travelling to the Stadium of Light for the first time since December 2016, when they lost 2-1 as reigning Premier League champions, Leicester have won just one of their last nine league fixtures on Wearside.
Given recent results, the Foxes could be forgiven for fearing a similar outcome on this occasion, as Enzo Maresca's once-unstoppable side have been beaten three times since the middle of last month.
After losing only one of their first 13 away games this season - and winning no fewer than 10 - Leicester have lost two of the last four ahead of Tuesday's trip to the North East, and they were surprisingly defeated at home by Queens Park Rangers on Saturday afternoon.
Just days after reaching the FA Cup quarter-finals by beating Bournemouth in extra time, and booking a last-eight tie with Chelsea later this month, Maresca's men were caught out by a QPR side currently scrapping for survival.
Though they dominated both possession and the shot count, Leicester had only Ben Nelson's second-half strike to show for their efforts in a frustrating 2-1 defeat, and after seeming nailed on for an immediate top-flight return, they now hold just a five-point advantage in the automatic promotion race.
Sunderland Championship form:
D
W
L
L
L
L
Leicester City Championship form:
W
W
W
L
L
L
Leicester City form (all competitions):
W
W
L
L
W
L
Team News
In addition to Corry Evans, Patrick Roberts and Niall Huggins, who will be absent for some time to come, Sunderland's top scorer Jack Clarke was recently ruled out for up to six weeks by an ankle injury.
Caretaker boss Mike Dodds gave 20-year-old Romaine Mundle only his second start on Saturday, while teenager Chris Rigg made a cameo from the bench, and both may be involved in midweek; Jobe Bellingham and Luis Semedo should start up front.
Meanwhile, Leicester midfielder Wilfred Ndidi is still sidelined, and hamstring injuries for Dennis Praet and Ricardo Pereira have also reduced Enzo Maresca's options.
The Foxes' head coach can call upon Jannik Vestergaard, though, as the Danish centre-back returns after serving a suspension.
Patson Daka or Tom Cannon could lead the visitors' front line, but veteran striker Jamie Vardy will push for selection, having scored four goals in his last five league games against Sunderland - including a brace at the Stadium of Light back in April 2016.
Sunderland possible starting lineup:
Patterson; Hume, Seelt, O'Nien, Hjelde; Styles, Ekwah, Neil, Mundle; Bellingham, Semedo
Leicester City possible starting lineup:
Hermansen; Choudhury, Faes, Vestergaard, Justin; Winks, Dewsbury-Hall; Fatawu, Akgun, Mavididi; Daka