A one-sided first half saw the Baggies take control of the clash and forced Wednesday to settle for a storm-weathering session with only Djeidi Gassama offering a great deal in terms of an outlet. The second half turned along with a system switch-up and Owls substitutes made a difference - with chances falling to the away side as the game went on.
A classy Adam Armstrong finish seemed to set up a home win before subs Svante Ingelsson and Callum Paterson combined to grab what could have been a dramatic equaliser - before Jason Molumby diverted a last-gasp corner home to take the three points.
Here are our ratings from another topsy-turvy afternoon with Sheffield Wednesday.
13. Pol Valentin - 6
On as Wednesday flipped to a five. Carded for an ugly one on Armstrong. Involved in some decent stuff down the right later on as Wednesday chased things. | UGC
14. Svante Ingelsson - 6
On before the hour. Brought something to a midfield that needed his legs. Belted about and put his foot in. | UGC
15. Iké Ugbo - N/A
On in the last minutes. One chance was well struck but was excellently saved by Wildsmith. | UGC
16. Callum Paterson - N/A
On in the final minutes and caused adequate chaos. Poked home what felt like the equaliser. | UGC