Saido Berahino, Lee Gregory and Barry Bannan gave the Owls a 3-0 lead in the first half before Tottenham Hotspur loanee Troy Parrott pulled one back for MK Dons before the break.
Though Darren Moore’s side were defensively disciplined throughout the second period, Scott Twine’s injury-time free-kick set up a nervy finish after the fourth official indicated there would be 10 minutes added on.
But fortunately for Wednesday the hosts couldn’t capitalise and they move up two places to fifth.
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2. Bailey Peacock-Farrell - 7
Played his part in Bannan's goal with a long ball upfield that MK Dons failed to properly deal with. No real chance with either goal and saved well from Twine in the second half before the forward's brilliant free-kick late on. Commanded his area well all night with plenty of good collections from crosses. Photo: Steve Ellis
3. Liam Palmer - 7
Made a welcome return to the starting XI and underlined his worth with a key block during a rare MK attack in the first half. Did get away with one when his clearance fell to Parrott, who wrongly chose to pass instead of shooting. Photo: Steve Ellis
4. Harlee Dean - 6
Will be gutted to have had to come off, especially with the Owls conceding moments after his departure. Had little to deal with before his untimely exit. Photo: Steve Ellis