Oli McBurnie scored a penalty in the 103rd minute to earn Sheffield United a 2-2 draw and potentially crucial point against West Ham.
The Premier League's bottom club looked set to be left empty handed and rueing missed chances after James Ward-Prowse had struck from the spot for the visitors. But West Ham goalkeeper Alphonse Areola clattered half-time sub McBurnie following a cross into the box - injuring himself in the process - and McBurnie converted the penalty.
It is the latest goal scored in the Premier League, according to Opta records dating back to 2006. But incredibly there was more drama to come, with Anel Ahmedhodzic seemingly pulling Jarrod Bowen to the ground in the Sheffield United area just before the final whistle, but the decision went the other way, to the disbelief of Hammers boss David Moyes.
By that stage both sides were down to 10 players, with Rhian Brewster and Vladimir Coufal sent off in stoppage time as desperation set in for both teams.
Earlier Ben Brereton Diaz marked his Premier League debut with an equaliser for the Blades on the stroke of half-time, cancelling out Maxwel Cornet's first goal for the Hammers.
But the Chilean dragged a one-on-one chance badly wide in the second half as Sheffield United struggled to turn their possession and territory into a second goal.
They were then hit against the run of play when Danny Ings - West Ham's standout performer on the day - was brought down by Gustavo Hamer and Ward-Prowse sent Wes Foderingham the wrong way.
But there was the late, late twist to come and while Sheffield United stay bottom they are into double figures with 10 points and seven from safety. West Ham remain sixth, five points behind Tottenham in fifth.
- How the teams lined up | Match stats
- Live Premier League table | Fixtures | Results
- Watch free Premier League highlights
- Stream Sky Sports with NOW | Get Sky Sports
How Sheff Utd earned a valuable point...
Before the late drama, it was a story of two players scoring their first goals for their clubs in the first half.
Cornet has had to wait 31 matches to break his duck for West Ham and his delight was plain to see when he lashed in at the back post after Ings' shot deflected kindly into his path. It was a hammer blow for Sheff Utd who had dominated until that point.
Early chances had come and gone for Hamer, Vinicius Souza and Andre Brooks, with Jack Robinson's long throws causing trouble. Auston Trusty had the best of those chances, planting a free header from a corner straight into the arms of Areola moments before Cornet struck at the other end.
But Brereton Diaz showed why Chris Wilder had put his trust in him on 44 minutes, pouncing on the loose ball after Areola brilliantly parried William Osula's header and blasting in his first goal since May.
McBurnie came on for Osula at the break and was inches away from latching onto a James McAtee cross early in the second half as the home side picked up where they had left off. He had the ball on the roof of the net moments later.
Brereton Diaz's failure to double his tally when McAtee played him in felt like it could be decisive and, despite the momentum being firmly with the home side, it was West Ham who struck next.
The challenge from Hamer on Ings was clumsy and there was no debate about the decision. Ward-Prowse's conversion seemed to have settled it.
Sheffield United's frustration at the way things had gone was summed up when Brewster flew into a challenge on Emerson. After a check of the pitchside monitor ref Michael Salisbury unsurprisingly upgraded the yellow to a red. Coufal got himself booked in the aftermath. He soon got his own marching orders for catching McAtee.
Moyes refused to look at Coufal as he walked past him. He was incensed moments later when the set-piece led to McAtee crossing into the box and Areola taking down McBurnie for the equalising penalty, scored past replacement keeper Lukasz Fabianski. The even later call not to award Bowen a third spot-kick of the game will have soured his mood further. But delight and optimism was the feeling for the home side.
Wilder delighted with his Blades
Sheff Utd boss Chris Wilder: "I'm delighted we stayed in the game because when they were rolling the ball around it could have quite easily have gone from 2-1 to 3-1. But we put some fabulous blocks in there which gave us the opportunity at the end.
"The penalty on Danny Ings, clumsy challenge. Nothing really in it. Brewster's tackle - I'll see it one way others will see it the other. When we played Brentford we had one 10 times worse on Souza.
"Their goalkeeper comes and makes a rash decision and we get the penalty. I'm delighted we got something from the game. From a stats point of view we were good. We controlled the game first half. Second half we missed a good chance to go up in the game. We didn't find that bit of magic.
"Overall we've had a decent afternoon. We've not got the three points we wanted but a point against a team sixth in the division."
On Brereton Diaz: "He's disappointed he's not got a second. It's a fabulous run and he's in. He was down to play 55-60 minutes. I think it was just over that when he had that opportunity. He was just flagging a little bit. Hopefully we can get him up to speed and chances like that I'm sure he'll stick away. But he can be delighted, I thought his performance was excellent. He's got all the characteristics to be a Sheffield United player."
Moyes airs frustration with refs: Areola was fouled
West Ham boss David Moyes: "Disappointed we didn't win the game in the end. We dropped two points today. It would have been a big two points for us. We played against an improved Sheffield United, who have run a lot of teams close recently. Obviously they saw this as a really important game for them as well because of their position.
"I'm certainly not going to talk about any of the referees, that's for sure. I'll only get myself in trouble.
"We've got to a stage now where we're settling for a level of officiating which we're shrugging our shoulders and saying, 'yeah OK'."
On whether Areola was fouled for the Sheff Utd penalty: "Absolutely, he was completely fouled, yes."
On the late penalty shout from Bowen not being given: "I'm shrugging my shoulders again. We don't know what they're going to do."
On West Ham's performance: "My team's performance was so poor today. Maybe my worst... It was a wee bit of a throwback, the game, long throws into the box, loads of free kicks. We had to deal with it. But we never passed it well, especially in the first half.
"As the game went on we got a bit better. We had a great chance to go 2-0 up and 3-1 up. I'm more disappointed with our own performance than anything else.
"We had to find a way to scrap and get through it. We were missing a few players who might have added a bit of quality to us but we had to juggle the team. It got us in front and we should have seen it out."
What's next?
Sheffield United's next game is at home to Brighton in the FA Cup fourth round on Saturday January 27; kick-off 3pm.
The Blades then travel to Crystal Palace in the Premier League on Tuesday January 30; kick-off 8pm.
West Ham are next in action at home to Bournemouth in the Premier League on Thursday February 1; kick-off 7.30pm.
The Hammers then travel to Manchester United on February 4, live on Super Sunday; kick-off 2pm.