James Hanson scored a 15-minute second-half hat-trick as Walsall slumped to their heaviest league defeat of the season at Bradford.
The Bantams dominated throughout, with Filipe Morais' 54th-minute opener and Hanson's first career treble securing a resounding win.
Walsall drop a place to fourth in League One and are now six points off the automatic promotion places, albeit with a game in hand.
Head coach Jon Whitney made three changes to the Walsall team that were held to a 1-1 draw by Swindon in midweek.
Jim O’Connor, Liam Kinsella and Andy Taylor came in, with Milan Lalkovic dropping to the bench and Jason Demetriou missing out through injury.
Matthew Pennington was not involved after he was recalled by his parent club Everton.
Eyeing a sixth successive home success, Phil Parkinson’s Bradford started the brighter and should have taken an 11th-minute lead.
Morais’ fine cross picked out Lee Evans but his free header was too close to Neil Etheridge, who saved with his leg from point-blank range.
The Saddlers keeper thwarted the Bantams again shortly after, beating away Tony McMahon’s half-volley at his near post.
Bradford were in the ascendancy but, against the run of play, Walsall went mightily close to making the breakthrough on 21 minutes.
Jordy Hiwula exchanged passes with Sam Mantom on the edge of the box before crashing a fierce left-footed drive against the bar.
Kyel Reid’s deflected strike was then gathered by Etheridge, before Andy Taylor fired off target from a short free-kick at the other end.
The play-off chasing hosts were looking dangerous and they would have led at half-time but for some determined defending from Paul Downing.
Evans intercepted Sam Mantom’s sloppy pass, drove forward and unleashed a firm low strike which Etheridge could only parry.
The ball rolled invitingly for Morais, who looked certain to score, but Downing made a crucial, goal-saving challenge to divert his effort behind.
HALF-TIME: BRADFORD 0-0 WALSALL
Roared on by a vocal home crowd, Bradford flew out of the traps after the resumption and put Walsall under sustained pressure.
Etheridge twice frustrated McMahon in quick succession, first parrying a curling 25-yard free-kick before turning away a near-post drive.
The home side were well on top, with the dangerous Hanson then rising highest from a McMahon set-piece but heading over.
A Bantams goal appeared inevitable and on 54 minutes one duly arrived, as Morais poked in following a goalmouth scramble.
Walsall were seriously under the cosh and just three minutes later, they were given a mountain to climb.
A long ball found Hanson, who bundled his way past Downing, cut inside O'Connor and finished confidently into the bottom corner.
The shell-shocked Saddlers would have fallen further behind but for a fine reaction save from Etheridge who tipped over Rory McArdle’s header.
The over-worked custodian was extended once again shortly after as he kept out Morais’ stinging left-footed drive.
Walsall almost pulled one back, Hiwula with a dipping, 30-yard half-volley which the back-peddling Ben Williams acrobatically tipped over.
But Bradford put the result beyond doubt on 72 minutes, as Hanson nodded home from a McMahon free-kick.
And the hosts added a fourth barely a minute later, Hanson completing his hat-trick with a close-range header from Morais’ left-wing cross.
The Saddlers’ misery was almost compounded in stoppage time, but Josh Cullen’s effort was pushed away by Etheridge.
FULL-TIME: BRADFORD 4-0 WALSALL
Etheridge, Kinsella, Downing, O’Connor, Taylor, Chambers, Mantom (Morris 70’), Forde, Henry (Bradshaw 59’), Sawyers, Hiwula (Cook 82’).
Subs not used: MacGillivray, Lalkovic, Preston, Sangha.
19,336 (686 Walsall supporters).