Gary Madine struck an injury-time equaliser to prevent League 1 strugglers Walsall completing an archetypal smash and grab at Hillsborough.
Despite the Owls taking control of the game from the first whistle, the points seemed destined for the Bescot as second half goals from Jon Macken and Jamie Paterson put the visitors in front.
Ryan Lowe found the target for the hosts in between and Madine struck with the last kick of the game to prevent former SWFC captain and current Walsall boss Dean Smith returning home with the points.
Wednesday dominated the top v bottom contest, creating a hatful of chances in the first half alone.
Michail Antonio twice struck the crossbar, in addition to which a raft of openings were created by the home side.
The first opportunuity fell to the in-form Lowe, who lofted over the bar following a dangerous set piece delivery from Chris Lines five minutes in.
Lowe almost found a way through ten minutes later when Rob Jones headed namesake Mike's cross back across goal but the striker's volley fell just the wrong side of the woodwork.
It was all Wednesday, though, as was evidenced by the electric Antonio on 16 minutes.
The loanee winger took a clever flick from&nbsp;Madine into his stride before unleashing a thundering drive from distance that brushed the top of the bar with keeper David Grof beaten.
Antonio went closer still on the half-hour mark after a sublime feed from Madine set the winger scampering in on goal down the right channel.
The Reading man took his aim early and pulled the trigger on another piledriver that this time rattled the crossbar full-on and rebounded to safety.
The one-way traffic continued - until 11 minutes before the break when Walsall could and perhaps should have taken the lead with their first meaningful attack.
Lee Beevers sent a teasing cross right into the heart of the danger zone, where Alex Nicholls had time and space in front of goal but somehow failed to get a connection.
The game soon reverted to type, however, and the Owls saw out the opening 45 with a Lines free kick that brushed the top of the net, much to the relief of the visitors, who headed down the tunnel on level terms.
Wednesday started the second half as they ended the first, taking the game to Walsall, but were stunned by a counter on 58 minutes that gave the Midlanders the lead.
Florent Cuvelier escaped down the left flank and cut inside to set up the onrushing Macken, who blasted home from ten yards.
But the joy was short-lived for Smith's side as they promptly conceded within two minutes of the restart.
A Lines corner found its way to the back post and Lowe turned to drill a daisycutter into the back of the Kop net.
The Owls introduced Jermaine Johnson just past the hour, the pace ace having missed around a month of action with a knee ligament strain.
But it was fellow wideman Antonio who continued to cause problems for the Walsall defence, forcing one fine save in particular from Grof on 69 minutes.
Johnson still vied for a piece of the action and a trademark run and shot ended with an agonisingly close finish that brushed the top of the net.
But just as the Owls looked to be back in the box seat, the Saddlers struck out of the blue for the second time.
And the goal came from nowhere on 72 minutes, with little seemingly on for Paterson when he took possession down the right channel.
But the midfielder burst inside and hit a superb shot across Stephen Bywater that rippled the Leppings Lane net.
The Owls launched straight back into attack and Johnson went close with a deflected effort that Grof did well to smother.
The Hungarian custodian came to Walsall's rescue moments later, this time keeping out a hard and low drove from Antonio.
As the clock ticked down, the feeling was one of this not being Wednesday's night, but Madine beat Grof in the 95th minute with a sweet shot that ensured Dave Jones' start as Owls boss remains unbeaten.
Owls: Bywater, Buxton, R Jones, Batth, Bennett, Antonio, Semedo, Lines, M Jones (Johnson 63), Madine, Lowe (O'Grady 81)
Unused substitutes: Jameson, Llera, Prutton
Walsall: Grof, Sadler, Butler, Smith, Macken (Bowerman 90), Hurst, Beevers, Paterson (Westlake 90), Nicholls, Cuvelier, Mantom
Unused substitutes: Walker, Lancashire, Ledesma