Scunthorpe 2 Sheffield Wednesday 0: Reality kicks in after Owls' unbeaten streak is ended
After successive wins in his opening three games, the Owls had climbed out of the Championship relegation zone but in a scrappy clash with fellow strugglers Scunthorpe United it was the hosts who showed the clinical touch in the penalty area.
First Gary Hooper fired home after just 79 seconds before Grant McCann snatched a late second on the break after long periods of possession by the Owls.
"I think we deserved something out of the game. It was a horrendous start and I'm disappointed about that," said Irvine.
"I'm not going to be too critical, we will hopefully learn. We were on the back foot for the first 20 minutes or so and I thought we got a grip of the game from then on.
"We got in the final third a lot and you have to give credit to Scunthorpe, they defended their box very well. Maybe we needed a bit more quality to open them up. We huffed and puffed a lot but we didn't look like we were going to score a lot of goals.
"The lads realise where we are. We're obviously in a relegation battle and are aware of that. We need to keep that in mind until we get ourselves safe, if we're able to do that."
Irvine stuck with the same side which beat Peterborough on Saturday meaning there was still no place in the squad for injury-hit Francis Jeffers.
That meant a starting place for Tom Soares after the Owls struck a deal to keep the Stoke City midfielder on loan until the end of the season.
Wednesday were caught cold inside the opening two minutes. Right-back Lewis Buxton played a sloppy pass in his own half, Paul Hayes curved a delightful pass through the middle of the defence and Hooper fired low beyond Lee Grant.
It was Hooper's 10th goal of the season, and he nearly added to that total but his effort was deflected wide.
Wednesday had struggled to start, and the closest they came to troubling Iron goalkeeper Joe Murphy saw Leon Clarke fire in a low shot after good work from Marcus Tudgay.
Murphy had to be alert to tip over Michael Gray's shot, but the Owls midfielder had strayed offside anyway.
Scunthorpe's electric start seemed to have caught Wednesday flat-footed, maybe the visiting players had not spent their Sunday afternoon tucked up in front of the television as the Iron – struggling in the Championship – put in a super performance against the millionaires from Manchester City.
The Owls had enjoyed plenty of possession, but too often pumped the ball forward onto the heads of the towering home centre-backs with Rob Jones dominant.
And the visitors were indebted to Grant for keeping them in the game on 34 minutes, tipping McCann's powerful 25-yard shot over the crossbar.
Without the pace of the injured Jermaine Johnson, Irvine had opted for a more compact midfield, hoping the guille of Soares and Gray could unlock the Iron defence.
On-loan Soares, who opened his Owls account a week earlier against Blackpool, looked the most likely to create an opening but the final ball into the penalty area let them down.
Wednesday came out with far more purpose after the break, no doubt with Irvine's words ringing in their ears, and they attacked the end where 2,000 travelling Sheffield fans gathered.
Clarke was chasing every loose ball, even bowling over Iron goalkeeper Murphy but referee Mark Clattenburg kept his cards in his pocket. Darren Potter and Gray wasted good set-play positions, and Tommy Spurr was unlucky when his volley struck an Iron defender and looped away for a corner.
Play had been camped in the home half for the first 15 minutes of the second half as Wednesday kept possession, but the lack of a clinical finisher was highlighted when Gray latched onto a long through-ball but snatched at his shot and it flashed wide of Murphy's left-hand post.
With 70 minutes gone, Murphy still had to make a save and Irvine threw on an extra striker, Luke Varney, in place of Soares.
And it was the former Crewe striker who nearly created an Owls goal, but his whipped-in cross was chested wide by Tudgay, who was unable to get his head to the ball in time.
At the other end, good work from Hayes set up a chance for Garry Thompson but he dragged his effort wide, before McCann got on the end of an Iron break to smash home at the second attempt in the 77th minute.
Varney flashed a shot wide, Tudgay's effort was blocked in the area and substitute Etienne Esajas failed to pick out a team-mate after a tricky run down the left flank as Irvine tasted his first defeat as Wednesday boss.
Scunthorpe United: Murphy, Williams, Togwell, Byrne, McCann, Hayes, Hooper (Forte 80), Thompson, Jones (Moloney 68), Mirfin, Woolford (Wright 62). Unused substitutes: Lillis, Sparrow, McDermott, Morris.
Sheffield Wednesday: Grant, Buxton, Purse, Beevers, Spurr, Soares (Varney 66), O'Connor (Sodje 80), Potter, Gray (Esajas 74), Tudgay, Clarke. Unused substitutes: Jameson, Simek, Hinds, McAllister.
Referee: M Clattenburg (tyne and Wear).