Sheffield United had been accused of throwing in the towel in their battle for survival.
On this evidence, there is plenty of fight left in Chris Wilder's side yet. Wilder refused to call this relegation six-pointer a 'must-win', but defeat here would surely have ended their slim hopes of avoiding the drop.
Instead, the Blades chose the perfect time to record their first league victory on the road as they ripped up the formbook and cut the gap to Luton to seven points.
Game on. Two goals in six first-half minutes put them on course. Cameron Archer had produced one of the misses of the season but made immediate amends seconds later with what could turn out to be a vital strike in Sheffield United's campaign.
Archer took advantage of a mistake from Gabriel Osho, nipped in and finished with aplomb.
The relief was there for all to see. Then VAR intervened. Referee Chris Kavanagh adjudged Reece Burke to have handled in the area when blocking a Vini Souza header and awarded a penalty, cooly converted by James McAtee.
Early in the second half, Luton got a spot-kick of their own in similar circumstances, with Kavanagh giving handball against Souza after being told to go to the pitchside monitor.
Carlton Morris did the rest to halve the deficit. Now it became a test of Sheffield United's mettle, and thankfully for Wilder and the 1,350 travelling fans, it was one they passed.
As Luton went in search of an equaliser, the visitors countered. Ben Osborn fed Souza, whose right-footed drive found the bottom corner 18 minutes from time.
Cue pandemonium in the away end. 'Come on Vini Souza, join us in the boozer,' they sang as they prepared to celebrate on the long trek home.
Sheffield United will have had painful memories from when these two last
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