Sheffield United 1 Watford 0: Hard work rewarded as Oli McBurnie and the Blades do the necessary
It was a 1-0 win secured by a Hornets defender nutmegging his own goalkeeper.
The game ended with a scramble in front of the Blades goalmouth in the sixth and final added minute.
It had been hard work and the reception the home players got at full-time reflected that.
But the point was, the Blades got the job done. After back-to-back defeats, the details were neither here nor there.
Watford certainly caused a few scares but at full-time the cushion to the Championship promotion places was back to seven points with a game in hand.
It was a pity in a way that the goal, scored after 73 fraught minutes, had to be debited to Porteous because a good deal of the credit was owed to Oli McBurnie.
It was his lovely throughball Sander Berge took his time over, waiting for a glimmer of light to put the ball into as the angle tightened.
Daniel Bachmann kept out his shot, but at the expense of a corner delivered to McBurnie at the far post. When he played it back in, Porteous applied the unfortunate finish.
As the goals were flying in for Championship leaders Burnley and past third-placed Middlesbrough, the first half at Bramall Lane promised more than it delivered.
Keinan Davis let the hosts off the hook and flickers from Iliman Ndiaye not enough for a shot on target. The Hornets did not have one either.
The best chance of the first 45 minutes fell to Davis when Anel Ahmedhozic fouled Joao Pedro out wide and picked up a booking. The centre-forward was in too much space from Ken Sema's free-kick, but headed it wide.
Mario Gaspar had a good chance too after only four minutes after finding himself in a similar amount of space at the back post, only to volley way off target.
Another free-kick out wide and another booking – this time for Max Lowe bringing down Ismaila Sarr on the other wing – brought another nervy moment, Wes Foderingham touching away Imran Louza's delivery but grateful the loose ball got caught in a tangle of legs.
A couple of chances fell to Lowe under pressure at the other end, shooting off target after a Jack Robinson long-throw pinballed about, and then when a corner ended up with him.
Ndiaye's excellent 12th minute turn showed what the Blades were capable of, releasing the ball at the last possible second for maximum reward at the cost of a clobbering from Wesley Hoedt. Sander Berge worked the ball to Jayden Bogle, whose shot was blocked.
Ndiaye shot over when McBurnie won a good flick-on and John Fleck – on his first start since November – burst through. As the ball came loose, the Senegal striker's touch created the space to shoot, but he could not finish it.
But Watford were not allowing Oliver Norwood to conduct the game as he likes to from the base of midfield, so when he started to see more of the ball after the restart with his team-mates seemingly energised by whatever was said or shouted at them in the break, things looked better for the home team.
Bogle's 48th-minute shot took a touch which rendered it harmless but it was at least on target. So was Norwood's 55th-minute free-kick, awarded after a considerable delay as Keith Stroud realised Porteous had pulled McBurnie's shot.
Bogle had a shot blocked at the end of a move which saw him play a one-two with McBurnie with a gorgeous backheel.
Even then, the Blades were still insecure at the back.
John Egan had to make a tremendous block on Sarr after Ahmedhodzic was caught under a pass. A James Morris cross bounced off Davis, who should have more say over its direction.
Even though Bogle's 63rd-minute goal was disallowed for offside, reacting well to head in a full-blooded Ahmedhodzic volley at goal, it gave the Blades confidence.
Ndiaye had a shot beaten away and Bachmann saved the follow-up from substitute Ben Osborn.
When Ndiate showed great feet to get away from Gaspar, McBurnie could not quite pick the pass back to him but he got it right for Berge and that, ultimately, would be decisive.
Watford will probably overlook their lack of cutting edge and dwell on how they deserved better but for the Blades it was job done. End of.
Sheffield United: Foderingham; Ahmedhodzic, Egan, Robinson; Bogle, Berge, Norwood, Fleck (Doyle 61), Lowe (Osborn 61); Ndiaye (Jebbison 90), McBurnie (Sharp 79).
Unused substitutes: Davies, Basham, McAtee
Watford: Bachmann; M Gaspar, Porteous, Hoedt, Morris; Choudhury, Louza (Kone 59); Sarr, Joao Pedro, Sema (Assombalonga 78); Davis (Araujo 81).
Unused substitutes: Cathcart, Bacuna, Kabasele, Okoye.
Referee: K Stroud (Hampshire).