A return to domestic duty proved to a relatively straightforward afternoon for Celtic as a league win provided a short-term fix to the ails of the perennial European hangover.

A first-half opener from Tom Rogic and a second-half brace from Leigh Griffiths gave the visitors a welcome three points and provide respite from a turbulent week in the Europa League. Nir Bitton headed a fourth in the late stages to restore Celtic's three-goal advanatge after Tony Dingwall had pulled one back for the hosts.

The only moment of disquiet was the minute's silence for Remembrance Sunday which was interrupted by a small minority of travelling supporters.

Kieran Tierney, the only player who gained passmarks from his manager on Thursday night against Molde, was benched while Efe Ambrose and Dedryck Boyata took over the central defensive duties in the continued absence of Jozo Simunovic.

Tyler Blackett, hooked after coming on as a substitute on Thursday night, did not make the squad at all.

For long periods in the opening half it was a stodgy game played out on a pitch that had been saturated by the deluge of rain which had fallen torrentially before kick-off, meaning that underfoot conditions were parrticularly treacherous.

Openings were few and far between for either side, although Tom Rogic and James Forrest combined to allow the latter to unleash an attempt to whizz just past the right-hand post.

Ross County slowly emerged into the game and a corner kick, clearly worked on in the training ground in an attempt to exploit Celtic’s weak centre, should have asked far more questions from Celtic than the sclaffed attempt at the back post that Martin Woods hit.

The goal that opened things up came when Mikael Lustig and Rogic linked up before the Aussie, who will return to his home city of Canberra this week for international duty, blasted into the back of the net.

Leigh Griffiths came close to adding a second shortly after the restart, but was denied by a decent block from Gary Woods in the Ross County goal.

It was a warning, though, that the hosts failed to heed as the Scotland internationalist was allowed to net a double in a two-minute period that put the game to bed.

The striker’s 17th and 18th goals of the season – his league tally stands at 13 – were the strikes that restored normality to Celtic, yet the goal they shipped to 20-year-old Dingwall just minutes after netting the third incurred the wrath of Deila.

Ultimately it did not have any significant bearing on the game but it was a reminder, should one be required, that the soft centre remains a problem requiring attention. Similarly, the save that Craig Gordonn was called upon to make when he tipped an Alex Schalk header over the bar served as further notice that while Celtic can be relied upon to get the ball into the net, keeping it out remains the challenge.

Nir Bitton, however, ensured the final passage of play was as straightforward as the result as he netted a fourth to ease Ronny Deila out of what was a difficult week.

Worryingly, though, for Deila was the sight of James Forrest - who enjoyed a fine game - headed up the tunnel with an injury. Celtic, by that point, had committed all three subs and so the final few minutes of the encounter was played out with ten men, not that it duly troubled them.

ROSS COUNTY: Woods; Fraser, Robertson, Boyd, Foster; Gardyne, Irvine (Murdoch 76), Woods, McShane (Curran 58), Dingwall; Boyce (Schalk 66). Subs: Severn, Franks, Murdoch, De Vita, Holden.

CELTIC: Gordon: Lustig, Boyata, Ambrose, Izaguirre; Forrest, Rogic (McGregor 77), Johansen (McKay-Steven 70), Bitton, Armstrong; Griffiths (Ciftci 77). Subs: Bailly, Tierney, Allan, Cole.

REFEREE: Kevin Clancy

ATTENDANCE: 6042