The summer signing from Charlton struck in the 28th minute to cancel out Dutchman Etienne Esajas' stylish opener and went on to score again early in the second half after Sylvan Ebanks-Blake converted a penalty.

Substitute David Edwards made it 4-1 in the dying minutes as Wednesday's early-season optimism was all but shattered in the space of 45 minutes.

Wednesday's collapse coincided with Esajas' half-time withdrawal through injury, and Wolves themselves had cause for concern when captain Jody Craddock hobbled off early on.

Injuries forced Owls manager Brian Laws into making changes of his own. Akpo Sodje and Marcus Tudgay – who each scored twice in the 4-1 win over Burnley – were out of contention, leaving Deon Burton as a lone frontman.

Esajas stunned Molineux after 15 minutes with a curling left-footed drive from the edge of the box which nestled emphatically in the right corner of Wayne Hennessey's goal. But in the 28th minute, Iwelumo rose highest to connect with Foley's swinging cross and power a header into the bottom left corner.

Laws' luckless injury situation significantly worsened seconds into the second period when Esajas pulled up and the game seemed to slip away from the Owls. Sean McAllister was adjudged to have brought down Matthew Jarvis inside the box and Ebanks-Blake blasted his penalty hard and low past Grant.

Five minutes later Iwelumo made it 3-1 for a now-rampant home side before Ebanks-Blake played in Edwards to slot home.

Laws was a disappointed man: "We came here with confidence from the first day. We created plenty of chances. But it was completely different in the second half. Wolves could smell that one or two had given up and that was criminal. It won't happen again, that's for sure."

Wolverhampton: Hennessey, Foley, Stearman, Craddock (Collins 7), Elokobi, Kightly (Edwards 86), David Jones, Henry, Jarvis (Keogh 75), Ebanks-Blake, Iwelumo. Unused substitutes: Ikeme, Vokes.

Sheffield Wednesday: Grant, Hinds, Beevers, Wood, Spurr, McAllister, Watson (Smith 68), O'Connor, Esajas (Clarke 46), Johnson (Boden 69), Burton. Unused substitutes: O'Donnell, Gilbert.

Referee: M Jones (Mansfield).

Man of the match: Chris Iwelumo.