Walsall endured a night to forget after shipping five in a chastening defeat at rampant Rotherham.
The Millers took the lead with their first meaningful attempt on 13 minutes, captain Lee Frecklington with a sublime dipping volley from 25 yards which sailed over a helpless Mark Gillespie.
Goalscorer Frecklington turned goal-saver three minutes later as he cleared Amadou Bakayoko’s close-range header from Erhun Oztumer’s pull-back off the line.
After almost conceding at one end, Rotherham scored at the other.
Ryan Williams was the architect, checking back and whipping in a teasing left-wing cross which Jon Taylor, making a run across Jon Guthrie, headed past Gillespie at his near post.
The Saddlers’ night went from bad to worse as United added a third on 24 minutes, Taylor bundling in from virtually on the line after Will Vaulks’ long throw wasn’t dealt with.
Vaulks was again the provider as relentess Rotherham made it 4-0 just past the half-hour, delivering an accurate right-wing cross which Frecklington headed expertly into the top corner.
Paul Warne’s goal-hungry side continued to press, with Williams galloping clear down the right before being denied by the legs of Gillespie, who then blocked the winger’s fierce left-footed volley.
With the words of boss Jon Whitney ringing in their ears, Walsall started the second period brightly and pulled one back on 49 minutes when Bakayoko stabbed home Joe Edwards’ corner.
Kieffer Moore went close to restoring the hosts’ four-goal advantage just before the hour with a rasping right-footed drive from 20 yards which whistled narrowly wide.
With victory pretty much assured, Rotherham took their foot off the gas in an uneventful second half in which goalmouth incident was in short supply.
Substitute Daniel Agyei drilled wide of the underworked Marek Rodak’s near post on 72 minutes, while Rotherham’s Darren Potter diverted Joe Mattock’s cross-shot over the bar.
The Millers put the gloss on a thoroughly-comprehensive win with two minutes left, ex-Saddler Anthony Forde crossing for the unmarked Frecklington to fire home and complete his hat-trick.
Team: Gillespie, Wilson, Donnellan (Cuvelier 32’), Guthrie, Wilson, Chambers, Edwards, Leahy, Oztumer (Morris 46’), Bakayoko (Agyei 71’), T Roberts.
Subs not used: L Roberts, Jackson, Ismail, K Roberts.
Attendance: 7,330 (280 Walsall supporters).