Without ever hitting the heights Dons were easily superior, star man being midfielder Jason Puncheon, who often strolled at will through the Walsall defence.
Both Jemal Johnson and Ali Gerba were on top form, creating chaos in a hesitant Walsall defence.
The visitors went in front after only six minutes, when Gerba won an aerial battle with Walsall central defender Emmanuele Smith and Johnson latched on the ball before beating Clayton Ince with a fine low shot from just inside the box.
Both sides lost a player midway into the first half, with the Dons defender Dean Lewington being replaced by Bondz N'Gala in the 25th minute and Walsall skipper Stephen Hughes being helped off looking badly dazed a minute later with Mark Bradley coming on in his place.
It was a comparatively uneventful first half, with the Dons dominating and Walsall having only two tame attempts on goal, Chris Palmer sending a 21st-minute free-kick straight into the arms of keeper Willy Gueret and Alex Nicholls also having a header comfortably taken by Gueret from a 45th-minute Smith cross.
Walsall looked a little more spirited in the second half and a 30-yard shot by Rhys Weston in the 56th minute was well saved by Gueret.
But the Dons emphasised their superiority three minutes later when Gerba headed home neatly from a cross by Johnson.
The Dons player was injured in the process, having collided with Ince, but recovered.
Walsall responded well and Nicholls had a good chance in the 66th minute, when Troy Deeney won the ball, but shot well wide.
There was a scare for Walsall two minutes later when the normally confident Ince palmed the ball against his own bar from Wright's corner. Almost immediately Ince went off apparently injured and was replaced by Rene Gilmartin.
In the 75th minute French winger Sofiane Zaaboub came on for Nicholls and immediately had a chance, but fired wide with his first touch.
With Milton Keynes seemingly holding back, Walsall began to create chances and Dwayne Mattis produced a good save from Gueret in the 76th minute.
Zaaboub had another chance in the 82nd minute, but this time his low shot was saved by Gueret. The Dons made things comfortable four minutes later when Wright scored after a shot by Alan Navarro had hit the post.