A performance full of zest in the first half and control in the second was enough for the Owls to comfortably allay fears of a swift return to League One.
At any stage they could have dropped back into the bottom three had Middlesbrough cancelled out either of their two first-half goals.
But so impotent were Boro, so devoid of spirit and urgency, that they rarely threatened Chris Kirkland’s goal, allowing the Owls to keep the drop zone firmly in their rear-view mirror all afternoon long.
Steve Howard set Wednesday on the way with a thumping shot that crashed in off the underside of the bar after only seven minutes.
Then just after the half-hour, Lewis Buxton’s inswinging corner from the left-wing found the far corner of the goal. At first it appeared that Leroy Lita had glanced it home, but the Owls players ran over to Buxton to celebrate.
“Who cares?” shrugged Dave Jones afterwards. “Neither of them are on a goal bonus.”
Jones’s manner betrayed his emotions. He was relaxed, and although he probably would not admit it, a little relieved at steering Wednesday to safety.
He called the achievement greater than winning promotion last year.
“It’s a massive step forward, an almighty jump for the club,” continued Jones.
“My remit this year, although I wanted to get out of this division, was to stay in it, and that was always going to be a tall order.
“I can’t emphasise how hard a year it’s been. I’ve pulled, I’ve tugged, I’ve shoved, I’ve demanded from them, and I’ve flipped my lid at times. But they deserve an almighty slap on the back because it’s some achievement.”
Jones revealed that the previous Saturday’s dismal defeat to Peterborough, and the reaction of the Posh players and supporters, had galvanised his Owls team, who had failed to win in four games as they squandered a series of chance to ensure their survival.
“Last week I was a bit annoyed, people were talking to me as if we’d dropped into the bottom three, which at no point we were.
“At no time has there been talk of relegation in the football club, even when we were losing and going through that barren spell and couldn’t seem to get a win.
“We weren’t even playing that badly, it was just when would it turn.
“Since Christmas we’re probably in the top three in the form table and (Saturday) was just about putting the icing on the cake and the players delivered that.
“Last week they were poor and it was Peterborough’s day and they celebrated as if they were safe. That’s a dangerous game in this league. So I used that.”
It had the desired effect as a fired-up Wednesday tore into Middlesbrough from the first whistle.There were none of the nerves so commonly associated with teams in peril, with Howard’s seventh-minute strike quashing any chance of anxiety surfacing.
Jermaine Johnson – rated as only 50-50 by Jones in the build-up – played as if he knew his hamstring would only last him half an hour.
On one early run he scythed through the Boro defence, having begun in his own half, before his shot 60 yards upfield deflected wide.
The only surprise was that Johnson was not involved in the goal, the killer pass coming from Miguel Llera who picked out Howard. The 36-year-old turned on the ball, outsmuscled Rhys Williams and fired the ball home via the underside of the cross bar.
“It was a great finish, it’s what he’s all about,” said Jones of a man he picked up on loan from Hartlepool.
“When we brought him here people were saying ‘he hasn’t got the legs, he can’t run’ – but he never had the legs in the first place.
“He’s a target man, he uses his body, uses his strengths.
“Since the day he walked in he’s been a sheer delight to work with and I’m delighted for him.”
Johnson continued to keep Boro backtracking with his probing runs. On the opposite flank, Jeremy Helan was equally effective, linking up nicely with Danny Pugh who hit the side-netting as he fashioned a chance.
Curtis Main was Boro’s only threat, peeling off the back two of Llera and Anthony Gardner and giving them rare moments of concern.
The killer second goal arrived on 31 minutes, from Buxton’s corner.
Johnson, by this stage, was starting to clutch his hamstring and after a couple more bursts he was removed at half-time with his job well and truly done.
“For 20 minutes JJ was unplayable and then after that he might as well have sat with us,” laughed Jones.
“But he did his shift and I thank him for that because that’s what we asked him to do.”
Howard could have had a second before the break after Helan had rampaged down the left, but twice he was denied from close range by goalkeeper Jason Steele and then Williams.
Lita, within seconds of the restart, was then presented with a golden opportunity to seal the game, but he was thwarted by Steele. That was about as ambitious as Wednesday got after that as they settled for seeing what Boro could muster.
Very little was the answer, save for some good work by Grant Leadbitter and a penalty shout when Llera appeared to wrestle Williams to the ground.
The absence of any more drama left Owls fans in the 31,375 crowd to follow events at Huddersfield, Hull and elsewhere.
For Boro, this has been a worrying collapse. They could have gone top on New Year’s Day, but only three wins since saw them finish one point above Wednesday, who have battled relegation all season. That war has been won by the Owls, perhaps not as dramatically as how Huddersfield and Barnsley did it, but no less important.
“It looks easy now because we’ve finished four places up from where we were,” concluded Jones. “But it wasn’t.”
Sheffield Wednesday: Kirkland, Buxton, Helan, Llera, Gardner, Johnson (Lee 46), Prutton, Olofinjana (Semedo 56), Pugh, Howard, Lita (Maguire 83). Unused substitutes: Bywater, R Johnson, Taylor, Madine.
Middlesbrough: Steele, Bikey, Williams, Burgess; Hoyte, Leadbitter, Smallwood (Gibson 55), Halliday (Reach 66); McDonald, Carayol (Morris 66), Main. Unused substitutes: Leutwiler, Ledesma, Williams, Haroun.
Referee: A Haines (Tyne & Wear).