A 3-1 win over Chesterfield gave Wednesday their best home start to a season in 30 years.
A first half goal from Lewis Buxton and two after the break from Gary Madine and Ben Marshall did the damage as the Owls advanced to an automatic promotion slot for the first time this term.
Ex-Owl Leon Clarke scored on his return to Hillsborough but it was not enough and Wednesday head into next weekend's Steel City derby with Sheffield United full of confidence following this fourth win on the bounce.
All the early pressure came from the hosts, who forced a string of corners and almost scored from the third but ex-Owl Drew Talbot cleared the danger from Rob Jones' flick-on.
The pressure continued, which in turn spawned more corners, from which the Owls inevitably took the lead on 17 minutes.
Marshall sent a looping flag kick right into the danger zone and Buxton climbed high to nod beyond the outstretched Gary Fleming and into the far corner.
Marshall was proving a real handful to the Spireites' defence, with his penetrating runs down the right and through the middle causing problems.
At the other end, Chesterfield fans had to wait until the half-hour mark until their side truly threatened when Talbot did well down the flank and played in a daisycutter that fell the wrong side of the post.
The game soon reverted to type, though, and home debutant Chris O'Grady was a whisker away from getting something on Buxton's feed from the channel.
The first half ended with Mark Randall scuffing a promising opportunity wide, which summed up an unconvincing opening period for the visitors.
As a result, Chesterfield started the second half brightly and Clarke headed a good chance wide soon after the restart.
The Spireites pushed on and the Owls introduced Jermaine Johnson to up the attacking ante, which helped Gary Megson's men wrestle back the balance.
And on 59 minutes, Wednesday doubled their lead through the in-form Madine, who claimed his tenth goal in nine games.
There seemed little on for the striker when he picked up possession from O'Grady 20 yards out on the angle of the penalty area.
But Madine showed exactly why he heads the League 1 goalscoring table with a blistering hit that flew into the corner of the Kop net past a despairing Fleming.
The second goal took the wind from the Spireites' sails and with the clock ticking down, the closing exchanges seemed academic.
But Chesterfield suddenly gave themselves hope by halving the deficit with ten minutes to go when Randall sent in a corner that was converted by Clarke from close range.
But just as a frantic finish was on the cards, Marshall picked up possession down the left with three minutes to go before cutting inside to drill a low shot home that made sure of the points.
Owls: Bywater, Buxton, Batth, Jones, Bennett, O'Connor (J Johnson 53), Semedo, Lines, Marshall, Madine (McGoldrick 90), O'Grady (Sedgwick 72)
Unused substitutes: O'Donnell, Reynolds
Chesterfield: Fleming, Talbot, Howden, Downes, Grounds, Mendy, Allott (Whitaker 76), Randall, Westcarr (Bowery 46), Clarke, Morgan
Unused substitutes: Smith, Clay, Ford