Ross County’s resistance wore off as Celtic ran out comfortable winners in Dingwall.
The Staggies were undone by a familiar foe, with former Caley Thistle player Ryan Christie coming back to the Highlands to haunt his old derby rivals with a first-half double.
County had threatened a revival after Ross Stewart cancelled out Christie’s opener, only for the Scotland midfielder to restore the Hoops’ advantage before the break.
That laid the foundations for Tom Rogic and Michael Johnston to make sure of the victory with second-half strikes, as the Hoops continue to set the Premiership pace.
The outlook for the Staggies is a ninth successive match without a victory, keeping them three points off the bottom of the table.
Hibernian are the next visitors to Victoria Park on Wednesday, with co-manager Stuart Kettlewell refusing to dwell on the recent poor form.
Kettlewell said: “This is where we probably have a tendency to become so negative up here. There was always going to be a difficult period in the Premiership for us.
“I use the situation whereby if we got the start we had at this point, everybody would be upbeat and feeling great about themselves.
“Of course we want to be in better form and picking up more points.
“We are trying to find that solution but feeling sorry for ourselves and continuing to be negative is not going to help that situation.”
The contrast in form between the sides could hardly have been starker.
County were looking to end an eight-game winless streak stretching back to September, while the Hoops came into the game on the back of nine straight victories in all competitions.
Kettlewell and Steven Ferguson rang the changes, with four switches from the side which went down 2-1 to St Mirren the previous weekend.
Skipper Marcus Fraser, Billy Mckay, Brian Graham and the ineligible Ewan Henderson dropped out, with Richard Foster, Lee Erwin, Harry Paton and Keith Watson drafted in.
The Hoops were without talismanic leading scorer Odsonne Edouard but Neil Lennon’s men looked no less threatening than usual in the opening minutes.
Christie was inches from opening the scoring with a free-kick from the wide right, which clipped the inside of the near post, while Tom Rogic and Callum McGregor saw efforts blocked by the Staggies rearguard.
Celtic were handed the chance to take the lead on 11 minutes when Watson was penalised for bringing down Lewis Morgan inside the box. Nathan Baxter looked to have come to County’s rescue when he saved Christie’s initial penalty but was left despairing as the former Caley Thistle player tucked home the rebound.
It was an early setback but County were left with plenty time to recover and avoid a similarly crushing defeat to their last meeting with the Hoops when they were beaten 6-0 in Glasgow.
The Staggies showed a strong response, carving out an equaliser with their first meaningful attempt on 23 minutes. Josh Mullin’s free-kick into the box picked out the head of Stewart, who guided his ninth goal of the season past Fraser Forster.
The goal gave County a brief lift but Celtic restored their lead six minutes before the interval, with Kristoffer Ajer cutting the Staggies backline open with a threaded pass to release Christie, who tucked low past Baxter.
Celtic took command of the second half, which took time to burst into life and McGregor was inches from netting a third when his low strike came off the outside of the left-hand post.
Celtic wrapped up the points with a quickfire double within the space of six minutes. Rogic nestled a deflected shot into the corner after Christie allowed the ball to run into the Australian’s path, before a darting run inside from the left flank by Johnston culminated in the substitute sending a cushioned finish past Baxter.
Stewart should have had another goal but referee Nick Walsh wrongly ruled Brian Graham offside, deeming his obstructing of Christopher Jullien’s path rendered him active.
Kettlewell was frustrated, adding: “I’m not going to stand here and say it would have had any reflection on the game.
“It’s a tough enough task as it is in the Premiership, but to get decisions like that wrong to me is a farce.
“I have never seen an occasion where an offside is given by the referee without the linesman raising his flag to that point. It’s quite clearly onside.”