Walsall suffered a first league defeat of the season as they were beaten 1-0 at home to bogey-team Bury.
Craig Jones’ sixth-minute strike gave the Shakers victory – their first of the campaign.
Sam Mantom, Romaine Sawyers and Paul Downing each went close for the Saddlers but they couldn’t find a way past visiting goalkeeper Rob Lainton.
Walsall, the previous League One leaders, are now in second-place following Gillingham’s 1-0 victory over Doncaster.
The West Midlands Club have now failed to beat Bury in nine years – a run stretching back seven matches.
Dean Smith, the League One Manager of the Month for August, made five changes to the Saddlers’ starting XI.
Rico Henry, Paul Downing, Anthony Forde, Romaine Sawyers and Reece Flanagan were those to come in; Liam Kinsella, Matt Preston, James Baxendale, Milan Lalkovic and Kieron Morris all dropped out.
Anthony Forde registered Walsall’s first attempt inside the first minute, when he curled a weak 25-yard free-kick into the arms of Lainton.
Bury controlled the early exchanges and opened the scoring inside six minutes, when Craig Jones fired a firm angled drive into the far corner from inside the penalty area.
The Saddlers – chasing a fifth consecutive league win for the first time since 2005 – grew into the first half.
Reece Flanagan dragged a long-range attempt off target, before Rico Henry and Sam Mantom each had efforts blocked.
The latter then went close to an equaliser on 23 minutes, unleashing a thumping left-foot shot from 20 yards which Lainton parried at full stretch.
The visitors, who entered the match still winless in the league, were a threat on the counter-attack.
Downing blocked Danny Mayor’s goalbound shot, and Craig MacGillivray held Joe Riley’s powerful cross-come-shot.
Bury were indebted to Lainton on the stroke of half-time; first, he got down sharply to push away Romaine Sawyers’ low drive, and then he stopped James O’Connor’s far-post header.
HALF-TIME: WALSALL 0-1 BURY
Walsall started the second period purposefully, with Flanagan seeing an effort blocked and Sawyers then shooting wide from distance.
Mantom, who was nominated for League One Player of the Month, went close again on 58 minutes, but his right-footed rocket was expertly tipped away by Lainton.
Moments later, Peter Clarke made a superb goal-line clearance from Downing’s glancing near-post header.
The Saddlers – staring down the barrel of a first league defeat of the season – made a double change, with Morris and Jordan Cook replacing Flanagan and Forde.
Bury could have wrapped up the points with seven minutes of normal time remaining.
Former Port Vale striker, Tom Pope, broke into the penalty area and squared for Danny Pugh who, off balance, couldn’t find the target from 12 yards.
In the final minute of normal time, Lainton made another fine stop to keep out Mantom’s long-range strike.
Bradshaw then blazed a volley over the bar, and Lainton produced a smart reaction save to prevent Tom Soares from scoring an own goal.
As the Saddlers pushed for an equaliser, they almost conceded on the break.
Soares sprinted clear of Sam Mantom, advanced into the area but, one-on-one with MacGillivray, sliced badly wide.
FULL-TIME: WALSALL 0-1 BURY
Team: MacGillivray, Taylor, O’Connor, Downing, Chambers © (Lalkovic 76’), Mantom, Bradshaw, Sawyers, Forde (Morris 62’), Henry, Flanagan (Cook 62’).
Subs not used: Baxendale, Preston, Kinsella, Jezeph.
Attendance: 4,829 (440 Bury supporters).