Both Scunthorpe United and Sheffield United are staring the drop in the face ahead of their clash at Glanford Park and, realistically, the loser will see their already-slim survival hopes dealt an unrecoverable blow.
The Blades are only one place off Championship safety but, following Saturday's defeat in another six-pointer at Crystal Palace, they now lie five points behind the Eagles and survival. Meanwhile, Scunthorpe missed a great opportunity to secure back-to-back home league wins for the first time this season when they failed to beat out-of-form Derby.
The Iron have really suffered since Nigel Adkins' departure to Southampton, with their home form particularly horrendous.The have won only two league games at Glanford Park this season, and last week's surprise success over promotion-chasing Nottingham Forest was the first time Scunny had won at home since August.
Ian Baraclough has been the man in charge since Adkins moved south in September and the 40-year-old former defender has struggled to replicate his former colleague's success. There is no doubting that keeping Scunthorpe in the second tier would be a huge challenge for even the most experienced of managers and it is almost miraculous that Adkins managed to keep the side competitive at their current level.
The club have the lowest home crowds in the division by some distance - averaging more than 4000 less than anyone else - and their budget wouldn't look out of place in League One. Their fight against relegation in the past has been noble, and if Baraclough's side are to have any chance of somehow surviving and securing another unlikely season in the second tier, a win over their more illustrious near-neighbours tonight is a must.
If Scunthorpe are plucky and brave but ultimately destined to play below the second tier, then their visitors tonight are a polar opposite. Sheffield United make the short trip into Lincolnshire having failed to record a single win since the turn of the year.
Current boss and childhood Blades fan Micky Adams has only been in his dream job since December but is already under huge pressure, having only recorded four points in the dozen games since his move from Port Vale to Bramall Lane.
Unlike their hosts this evening, United have absolutely no excuses or reasons to be where they are. A club more than capable of punching their weight in the Championship, very few expected a squad and club of such calibre to be anywhere near the bottom three, let alone be staring down the barrel of third-tier football.
But football isn't played on paper, nor do sides win points for spending money or getting big gates, and on the pitch Adams, and Gary Speed before him, have failed to get the best out of the handsomely-paid playing staff.
Very few people would have highlighted tonight's game as a massive clash when the fixtures were released in the heady days of pre-season. Yet now, for Sheffield United at least, tonight is a game they dare not lose if they are to avoid dropping into the third tier for the first time since the dark days of the 1980s.
And for Scunthorpe, if they can manage to battle their way to a rare home victory, another miraculous survival may just be possible, but defeat would see their second spell in the Championship almost certainly come to an end.
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