The Saddlers’ five-match unbeaten run came to an end after a heavy defeat at promotion-chasing Bolton.
Erhun Oztumer’s 40-yard wonder strike gave the visitors a fourth-minute lead, only for Gary Madine to level ten minutes later with a diving header from Jay Spearing’s corner.
Jim O’Connor put Spearing’s cross through his own net to put Bolton in front and Liam Trotter’s deflected effort made it 3-1 on the half-hour.
Flo Cuvelier had a goal not given when his second-half attempt appeared to cross the line, but Bolton made sure of the win late on thanks to debutant Chris Long’s thunderous near-post drive.
The result leaves the Saddlers in 12th place, five points off the play-offs.
Eager to extend the unbeaten run to six matches, Jon Whitney’s men came flying out of the traps and took the lead in spectacular circumstances inside four minutes.
Oztumer received possession 40 yards out and unleashed a stunning left-footed half-volley which sailed over home keeper Ben Alwnick and into the top corner.
It was the diminutive playmaker’s 12 goal of a productive campaign – a truly special strike reminiscent of his lob from the halfway line at Swindon in October.
But the visitors’ joy proved short-lived, Madine heading Jay Spearing’s left-wing corner in off the post from close range to bring Bolton level.
The top-two hopefuls had momentum and completed the turnaround on 26 minutes.
Le Fondre’s downward header from another Spearing set-piece was hacked clear off the line by Joe Edwards - but the danger wasn’t fully cleared.
Spearing picked up the loose ball and delivered a low cross into the middle which a stretching O’Connor could only divert into his own net.
With the wind in their sails, Bolton then extended their lead on the half-hour.
A long ball was chested down by Madine for Trotter to hit a first-time 20-yard effort into the top corner via a deflection.
Half-time: Bolton 3-1 Walsall
The Saddlers had a good chance to reduce the deficit at the start of the second half.
A slip from Alnwick allowed Amadou Bakayoko to steal possession and round the keeper, but with the angle tightening, he was unable to find the target.
There was huge controversy just before the hour mark.
Oztumer threaded a perfectly-timed pass through to the marauding Joe Edwards, who squared for Florent Cuvelier to stab an effort towards goal.
The ball looked to have crossed the line before being cleared by Mark Beevers – but no goal was given, much to the Saddlers’ frustration.
Wanderers had opportunities to put the game to bed, with Le Fondre side-footing Filipe Morais’ cut-back wide and Madine firing too close to visiting keeper Neil Etheridge when clean through.
But the Greater Manchester club made sure of the win with three minutes remaining, when debutant Long lashed a thunderous right-footed drive past Etheridge at his near post.
Full-time: Bolton 4-1 Walsall
Team: Etheridge, Preston, O’Connor, O’Connell, McCarthy, Chambers, Osbourne, Cuvelier, Edwards (Randall 78’), Oztumer, Bakayoko (Jackson 78’).
Subs not used: MacGillivray, Laird, Dobson, Morris, Moussa.
Attendance: 13,610 (886 Walsall supporters).