Wigan kept their Premiership charge increasing their lead at the top of the Coca-Cola Championship and stretching their unbeaten start to the season to 14 games.
Strikers Nathan Ellington and Jason Roberts showed just why they are rated the best strike partnership in the division as they terrorised the Crewe defence.
The Duke grabbed a double to join Roberts on ten for the season and since they teamed up together they have hit 37 of Wigan's 52 goals between them.
Lee McCulloch celebrated his first Scottish cap giving Wigan the lead after 18 minutes to claim his fourth goal of the season.
Crewe defender Billy Jones was booked for a foul on Ellington and Jimmy Bullard doubled the punishment when he picked out Lee McCulloch at the far post with the free-kick and the former Motherwell striker headed it firmly home.
Wigan were denied what looked like a clear cut penalty when Bullard was brought down by Alex keeper Ben Williams after being played through by Roberts only for ref Mike Pike to brush aside the appeals.
But with the Championship leaders piling on the pressure, a second goal was inevitable and it arrived after 25 minutes.
David Graham threaded a great ball into the box, Ellington shrugged of the challenge from sub Richard Walker and blasted in from ten yards.
Williams prevented worse damage with excellent saves from Ellington and Roberts, but Wigan missed a good chance when Graham hammered wide after non-stop midfielder Jimmy Bullard set up the shooting chance.
Ellington fired in Wigan's third after 48 minutes from the edge of the area, but Crewe pulled one back in the 55th minute when Steve Jones cashed in on some uncharacteristic slack defence.
But Wigan wrapped it up with a real spectacular six minutes from time. Bullard raced from his own half before unleashing an unstoppable shot from 30 yards.