Second-bottom Ross County slipped six points behind hosts Motherwell who ran out rampant 5-0 winners in the Scottish Premiership.
The Dingwall team simply had no answer against their lethal hosts, who netted three first half goals to put the game out of reach.
On-loan Hearts midfielder Andy Halliday opened his Well account after just eight minutes and ex-County man Blair Spittal added a finely-struck second on 22 minutes.
Theo Bair’s penalty – his sixth goal in five league games – made it 3-0 at the interval and Spittal and sub Jack Vale added gloss with two further late goals.
There was no further damage in the second half, but this was a sore one for the band of 57 travelling away fans as their side slumped to their ninth successive game without a victory in all competitions.
St Johnstone, who face Hearts on Wednesday, are now their nearest rivals, sitting five points in front.
Five of Derek Adams’ recent signings started for the second game running and this was a sharp reminder of how tough this division can be, even at the lower end.
County’s last victory before tonight was a 3-0 result against the Steelmen on December 5, meaning they had gone eight games since with two draws and six losses.
The visitors arrived at Fir Park on the back of a 1-0 home reversal against St Johnstone and the need for a positive result was clear.
Adams, who replaced manager Malky Mackay in November, has failed to find a level of consistency from his team and will hope the seven new arrivals during the window will help turn around their fortunes.
They hold a six-point lead over basement side Livingston with a game in hand before the Lions’ trip to Kilmarnock on Wednesday.
Seven draws for Motherwell from their last 11 matches was halting their progress.
After a bright opening by both teams, who were unchanged from the weekend, County were unravelled as soon as the eighth minute.
Blair Spittal sparked an attack down down the middle, fed the ball out Theo Bair and his cross was met by Halliday, who slid in to convert his first goal since switching from Hearts on loan before making it a permanent move this summer.
T0 their credit, County responded and Simon Murray drew a save from Liam Kelly when he got a sight at goal.
County keeper George Wickens twice denied Bair in one-to-one challenges, but on 22 minutes Motherwell were two ahead and coasting.
Spittal found freedom on the left after Halliday picked him out and he swerved an angled drive beyond Wickens. It was a cracker and the home supporters were elated.
It got worse for the Highlanders seven minutes before the break when Motherwell were awarded a spot-kick after Will Nightingale tripped the advancing Harry Paton in the box.
Referee Matthew MacDermid immediately pointed to the spot and after a VAR check, Bair was not to be denied this time and his penalty sent Wickens the wrong way.
A half-time change for County saw defender Josh Reid replace Cameron Borthwick-Jackson, who is on loan from Slask Wroclaw in Poland.
Goal-hungry Bair sought his second of the night when he gathered the ball on the edge of the box on 53 minutes, but his effort had too much height to trouble Wickens on this occasion.
During a stop in play for a knock, James Brown and Murray had a heated exchange as they argued perhaps over how they could make an positive impact in this game.
A tame Jordan White shot straight at Liam Kelly was as good as it got.
In the dying embers, Spittal crashed home another top-notch long-range strike out of the reach of Wickens then debutant Vale latched on to a through ball to poke the ball home.
Motherwell’s focus swiftly turns to Friday’s Scottish Cup fifth round tie at Morton, while the Staggies are next in action next Wednesday away to Rangers in the league.
Player ratings
MOTHERWELL (3-4-2-1): Kelly 6, Mugabi 6, Butcher 6, McGinn 6 (Blaney 76), O’Donnell 6 (Devine 76), Zdravkovski 6, Halliday 6 (Miller 49), Gent 6, Paton 6 (Nicholson 76), Spittal 8, Bair 7 (Vale 80).
Subs not used: Oxborough (GK), Casey, Buyabu, Ferrie.
ROSS COUNTY (3-4-1-2): Wickens 6, Ayina 5, Nightingale 5 (Efete 62), Borthwick-Jackson 4 (Reid 46), Brown 6, King 5 (Sheaf 62), Jenks 6, Harmon 5 (Khela 71), Dhanda 6, Murray 6, White 5 (Sims 71).
Subs not used: Ross (GK), Loturi, Henderson, Brophy.
Referee: Matthew MacDermid.
Attendance: 3724.
Star Man: Blair Spittal.