The teams are two of four level on 20 points at the bottom of the division, with the hosts now sitting at the foot on goal difference following three straight defeats.
Match preview
Following their promotion back to the Scottish Premiership last season, Kilmarnock have experienced a tough campaign thus far, as they picked up just 15 points from their opening 17 games before putting up a somewhat encouraging run with draws against Motherwell and St Mirren either side of a 2-1 victory over Aberdeen after Christmas.
That saw Derek McInnes's side move away from the bottom spot in the Premiership, but they have since been unable to add another point to their tally in three further outings, albeit having faced a tough schedule as they were firstly beaten 2-0 by league leaders Celtic.
Killie then faced another unenviable test at home to second-placed Rangers and only suffered a narrow 3-2 defeat, having battled with 10 men for the final 30 minutes following Danny Armstrong's red card, as Joe Wright's 85th-minute goal was not enough to spark a comeback and force a share of the spoils, before they did at least manage to advance in the Scottish Cup with a 1-0 beating of Dumbarton thanks to Jordan Jones's finish in injury time.
Hoping to build on that win and pick up an important result in the fight for survival, they then made the trip to take on fellow strugglers Ross County, who went into the contest at the foot of the division and trailing by three points, but that gap would be scratched off as the hosts dished out a 3-0 beating and leapfrogged McInnes's men as a result, courtesy of goals from Eamonn Brophy, Jordan White and Yan Dhanda.
Although they now find themselves at the bottom of the division as a result of their tough run, Kilmarnock do remain level on points with Ross County, Motherwell and Wednesday's opponents, meaning that they would certainly climb with a victory and could see their position improved even further given how tight the bottom half of the league is.
Their visitors will also aim to give their survival hopes a boost with what would be a crucial midweek victory after a tough run of their own in recent weeks.
The Tangerines experienced a concerning first half to the campaign and went into the World Cup break with just 12 points on the board from 16 matches, but they would return in improved form, firstly drawing 2-2 at home to Hearts before beating fellow strugglers Ross County 3-0 as an early Connor Randall own goal initially had them ahead before Charlie Mulgrew and Craig Sibbald got on the scoresheet.
Liam Fox's side then made it consecutive three-point hauls as Tony Watt hit the only goal of the game in the final 10 minutes of their clash with St Johnstone, but they have been unable to maintain that form since, with just one point coming from their last three games, having also played Rangers and Celtic in that time.
After a 2-0 loss at home to Rangers, the Tangerines were held to a 2-2 draw away at Hibernian as Kevin Nisbet forced a share of the spoils with a 92nd-minute leveller, and they would head into the weekend's contest with Celtic on the back of a 3-0 beating of Stirling University in the Scottish Cup fourth round as Aziz Behich, Jamie McGrath and Glenn Middleton found the net.
Now following on from another 2-0 defeat in their latest outing against the leaders, in which Jota and Aaron Mooy netted goals early in the second half, Fox's men remain in a difficult position at the bottom end of the table and will be desperate to put some distance between themselves and the threat of the drop with what would be their sixth league win of the campaign and a second over Killie after drawing 1-1 away early in the campaign and thrashing McInnes's men 4-0 at Tannadice Park in November.
Kilmarnock Scottish Premiership form:
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Kilmarnock form (all competitions):
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Dundee United Scottish Premiership form:
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Dundee United form (all competitions):
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Team News
Kilmarnock will welcome winger Danny Armstrong back to action on Wednesday, after he served a one-match suspension at the weekend, and he should come straight back into the starting XI, having scored five and assisted five of their 19 league goals so far this term.
His attacking input has been heavily relied upon with frontmen Christian Doidge and Kyle Vassell yet to find the net, while Scott Robinson has only managed one thus far, meaning experienced forward Kyle Lafferty could come in from the outset as McInnes aims to increase their attacking threat.
Elsewhere, Alan Power and Liam Polworth should again play in the engine room, with Joe Wright and Ash Taylor expected to continue their partnership in the middle of the back four.
Dundee United could again be without key striker Tony Watt, who has scored four goals in 17 league appearances so far this term, as he has missed their last two Premiership outings with an injury concern.
In his expected absence, Steven Fletcher will again be relied on to lead the line, with fellow summer arrival Glenn Middleton likely to join the 35-year-old up front.
Former Manchester United man Dylan Levitt will continue to play a key role in the midfield, while Charlie Mulgrew will be vying for a starting berth in the back three after Liam Smith, Ryan Edwards and Scott McMann have been preferred recently.
Kilmarnock possible starting lineup:
Hemming; Mayo, Taylor, Wright, Waters; Jones, Polworth, Power, Armstrong; Vassell, Lafferty
Dundee United possible starting lineup:
Birighitti; Smith, Edwards, Mulgrew; Freeman, Levitt, Harkes, Sibbald, Behich; Fletcher, Middleton