Chris Wilder’s inspired substitutions made sure Sheffield United left West Ham United’s London Stadium with their unbeaten away record in tact.
Lys Mousset, the hero on Monday night against Arsenal, scored with his first touch after coming off the bench to rescue a point for the Blades just when it looked like the game was slipping away.
United had been far too wasteful in front of goal and will have been frustrated that it took so long to get past the West Ham defence.
They are now unbeaten in all five of their Premier League games away from Bramall Lane, winning one and drawing four.
Robert Snodgrass had put the Hammers ahead with a well-taken goal just before the interval.
But Mousset responded when Enda Stevens nodded the ball into the forward’s path and he caressed the ball into the far corner, sending the packed-out away end into raptures.
The result marks another great display on the road for Sheffield and the fact they could have taken all three points again highlights their top-flight credentials
Wilder made just one change from the side that had beaten Arsenal at Bramall Lane on Monday night.
Callum Robinson started in place of Mousset, and the 24-year-old had a golden chance to put Sheffield ahead and add to his one-goal tally in the Premier League this season.
Roberto failed to stop Chris Basham’s delivery from the right but Robinson completely miscued his header when he found himself unmarked five yards out.
That chance came after Jack O’Connell had headed the ball into the path of David McGoldrick but the Blades striker couldn’t divert his flick past Roberto from inside the six-yard box.
The Blades’ frustrations were compounded when Andriy Yarmolenko played Snodgrass in and the former Hull City man coolly slotted past Dean Henderson just before the half-time whistle.
The Blades had defended superbly and picked their moments well going forward until the opener.
The hosts had most of the ball in the first half but failed to fashion any clear-cut chances before Snodgrass put them ahead.
They came close when Felipe Anderson curled an effort just over the bar.
Wilder’s men had conceded just seven goals coming into the game - the joint-best record in the Premier League - but as they got forward more frequently early in the second half, gaps started to appear.
West Ham wasted two opportunities to double their lead, first when Yarmolenko dithered on the ball to allow United time to find their shape before Henderson stood up well to keep Anderson’s shot out.
George Baldock twice found himself in space on the right-hand side of the area at the other end but had one effort saved before slicing a great chance wide.
Sheffield weren’t the only side guilty of sloppiness in front of goal however, as West Ham missed a huge chance to regain the lead.
Pablo Fornals’s ball across the face of goal found Snodgrass at the back post but he struck the woodwork with just over 10 minutes remaining as it finished 1-1.
On Mousset being named a substitute, Wilder said: “It’s a difficult one but Lys is still not up to speed and it took a lot out of him on Monday.
“The easy thing is to keep the same team but I have to do the right thing. I thought he looked a threat when he came on and we were delighted he finished that opportunity.
“In the first half we were second to every ball. But our start to the second half was great, we dictated the game knowing we had to take a few more risks which we did.
“They had chances on the counter-attack and their manager will be disappointed not to put us to bed, but it was a deserved result.”