Wolves midfielder Alfred N'Diaye grabbed a dramatic injury-time winner as the Sky Bet Championship high-flyers ground out a hard-fought 2-1 victory against battling Barnsley.
Barnsley had looked set to secure a point at Molineux when Adam Jackson's 90th-minute strike cancelled out Bright Enobakhare's opener.
But N'Diaye, whose first touch of the ball when he was sent on was to set up Enobakhare, broke Barnsley's hearts when he slid home a cross from Leo Bonatini from 12 yards.
Enobakhare, who had ended a two-year goal drought with his match-winning strike in Tuesday's Carabao Cup tie against Bristol Rovers, came off the bench to end Barnsley's resistance in the 80th minute.
It looked to be good enough to secure victory but Jackson punished them when he volleyed into the roof of the net after Wolves had failed to clear a corner.
Barnsley did not look like a side who had lost eight of their last 10 away games but still ended up with nothing to show for their efforts.
Following a tepid opening spell, Diogo Jota wasted an excellent chance to put Wolves in control after 14 minutes.
He was unmarked at the far post when Ivan Cavaleiro lifted the ball over from the right wing but could not get his header on target and ballooned his effort well wide.
Barnsley forward Tom Bradshaw then wasted an even better chance to break the deadlock three minutes later.
He was only six yards from goal when Brad Potts found him with a left-wing cross but failed to get any real power on his header and it was comfortably collected by goalkeeper John Ruddy.
Barnsley were then left fuming on the half-hour when their appeals for a penalty were rejected by referee Jeremy Simpson.
Former Wolves winger Adam Hammill delivered a cross from the right and as Bradshaw moved towards the ball he appeared to be bundled over by the Wolves skipper Danny Batth, but Barnsley's pleas were swiftly dismissed by the well-positioned Simpson.
Having survived that scare, Wolves should really have taken the lead five minutes before half-time. Ruben Vinagre's right-wing cross was perfect for Cavaleiro but he somehow contrived to push his shot from eight yards beyond the far post off goalkeeper Adam Davies, who was making his 100th consecutive start for Barnsley.
Jota was then off target from long range before he turned provider to set up Bonatini after 73 minutes.
Bonatini failed to failed to take advantage of an excellent opportunity when he blazed his shot well wide before Enobakhare showed him the way to goal - and set up a thrilling finale.