Substitute Charlie Austin snatched a dramatic win for West Brom to beat Sheffield Wednesday 2-1 and maintain their two-point lead at the top of the Sky Bet Championship.
Austin's 88th-minute penalty came just at the right time for Slaven Bilic's side, who were coming heavy pressure at The Hawthorns before stretching their unbeaten run to seven games with their third straight win.
Hal Robson-Kanu's fourth goal in six games gave Albion a 10th-minute lead but Steven Fletcher's 58th-minute penalty appeared to salvage a deserved point for the Owls, who had Jacob Murphy sent off in time added on in a game where both teams hit the woodwork.
In an exciting start, Robson-Kanu sent a twisting header looping over the bar in the first 30 seconds, from winger Matt Phillips's cross.
Wednesday responded with a low cross from wideman Murphy, which the unmarked Fletcher was inches away from as he slid in at the far post.
The Owls continued on the offensive, forcing three corners in quick succession, and from the second of them, centre back Julian Borner's snapshot was deflected wide.
Then it was West Brom's turn to attack, and Filip Krovinovic curled wide from the edge of the box after a smart backheel by Robson-Kanu.
Albion took the lead when Matheus Pereira sent Robson-Kanu racing clean through with a reverse pass from halfway and the former Reading striker drew goalkeeper Keiren Westwood before calmly sidefooting home with his left foot.
The goal was all West Brom needed to start dictating the play and Wednesday had midfielders Kieran Lee and Sam Hutchinson booked for fouls on Krovinovic and Grady Diangana.
After an improvement from the visitors at the start of the second half, they levelled through Fletcher.
The spot-kick was awarded after poor play from Krovinovic, the midfielder allowing himself to be caught in possession by Lee, who he then appeared to trip as he lay on the ground.
Fletcher casually rolled the ball down the centre of the goal for his sixth goal of the season to end a six-match drought as goalkeeper Sam Johnstone dived to his right.
Robson-Kanu stabbed Phillips's low centre just wide from point-blank range as Albion tried to hit back immediately.
But the pendulum had suddenly swung in Wednesday's favour and they went desperately close to taking the lead.
Left-back Morgan Fox's header smacked against the bar from substitute Adam Reach's free-kick with Johnstone beaten.
Albion hit the woodwork on 87 when Austin's glancing header hit the post following Diangana's cross.
But Austin had not finished and his big moment came after Pereira was tripped by Westwood and the striker found the bottom corner from the spot.
Murphy saw red for lunging in on Diangana in the second minute of time added on.
There was still time for clean-through Diangana to be denied by Westwood as Albion finished strongly.
What the managers said...
West Brom's Slaven Bilic: "I expected this kind of game. I consider that a 'derby' game, because I really rate their team. They play on the front foot, they're aggressive, they engage. They don't have kids, not age but mentality. They're physical, with enough quality. You can make games easier or harder for you, but on paper this was one of the toughest games.
"They're extremely difficult to play against, so it's a great win for us. Apart from the first half when they had those short corners, it wasn't easy for us. I was pleased, though, with how we organised the attacks. We didn't create clear cut chances, but many times we were on the edge of the box trying to walk it in instead of trying a strike from 15 yards. It was good."
Sheffield Wednesday's Garry Monk: "The first half was quite even but in the second half we were the best team on the pitch. To create that amount of chances and not win that game, that's three games in a row, not not take any points from it is quite astounding.
"Everything in terms of the performance is there. The main parts, being ruthless and clinical, there were chances there to kill that game and unfortunately we conceded that poor goal at the end. That's three games in a row, we've discussed it and we know we can't continue in that way. So much of that game is exactly what we needed it to be."