Aaron Mooy (second from left) scored the pick of Celtic's goals

Celtic "won't put a ceiling on what they can achieve" after restoring their nine-point Scottish Premiership lead with a routine win at St Johnstone.

Rangers had cut the gap with their win on Saturday but Celtic pulled away again thanks to Andrew Considine's own goal and a Kyogo Furuhashi effort putting them two up inside 22 minutes.

Drey Wright's fine strike brought St Johnstone back into it but Aaron Mooy's chip re-established Celtic's two-goal lead and David Turnbull added a late fourth after Considine was sent off.

It edges Ange Postecoglou's side another step closer to retaining their title, with 13 games remaining, but the Celtic manager insists they will take it "a day at a time".

"What's worked really well is we don't look too far ahead," he said. "We've got a really strong squad. We'll look to the cup next week and take every challenge as it comes. We are not going to be putting a ceiling on what can be achieved."

St Johnstone remain seven points clear of the bottom two and played well in Perth, but that only serves to highlight some of the quality Celtic produced on a difficult surface to deliver another Premiership win.

Yet it was Callum Davidson's side that opened up the brighter with good organisation and intent. They had one or two opportunities to test Celtic's backline, failed to and were ruthlessly punished.

Kyogo has been prolific in delivering goals, many of them being the finishing touch. However, it was his ingenuity in a deep position to spray the ball wide to Daizen Maeda that paved the route to Celtic's opener.

Maeda interacted with Mooy, whose pass in behind was exquisite. That ushered Kyogo in on goal and the outcome was inevitable, albeit Considine got the decisive touch.

The home side had to hang in. Unfortunately, Alex Mitchell hung back as his colleagues advanced and that allowed Jota in behind. His cross found Kyogo and, guess what, he finished emphatically for his 22nd goal of the season. Prolific.

The expected canter to victory was soon interrupted, though. Celtic appeared to switch off for a second, affording Wright space, and he took full advantage by drilling a fierce shot from outside the box, which deceived Joe Hart.

Food for thought, but not for long. Celtic's third, before the break, was sensational.

Kyogo dropped deep again, released Jota into a dangerous area and Mooy reminded everyone of the fine form he is in with a delicate, composed lob over Remi Matthews. Those in blue could only look on in admiration at the Australian's sixth goal in eight games.

To their credit, St Johnstone kept at it and consistently showed moments of promise. But Celtic looked comfortable and capable of finding another gear should it be required.

Considine's afternoon took another bad turn in injury time when he upended substitute Oh Hyeon-gyu on the edge of the box and Turnbull drilled home as Celtic took one more step towards another trophy.

Player of the match - Kyogo Furuhashi

Kyogo's vision and delivery unlocked St Johnstone for the opener and once again he was on the scoresheet with his movement, energy and ability crucial to everything Celtic do

Pitch no problem as Celtic canter on - analysis

No matter the obstacle, Postecoglou has this Celtic side finding solutions. Some of their football on a difficult pitch was outstanding.

They faced an opponent who got a lot of things right but the outcome was never really in doubt.

Postecoglou talks about seeking constant improvement and sometimes one wonders where exactly that's required. Yet it's exactly what they seem to do as the season unfolds.

Mooy has proved to be an excellent acquisition despite many initially doubting where he would fit in. Right at the heart of things is the answer.

With so many performing at such a high level and Kyogo producing where it matters, Celtic really do look unstoppable on this form.

St Johnstone can take heart from the performance and look forward to a crucial period in which they will face a more favourable fixture list on paper.

What the managers said

St Johnstone manager Callum Davidson: "It's not often you play against Celtic, have four shots on target and they score four goals. A couple of the goals we lost were poor but we did a lot of good things.

"The 4-1 score flatters them a little bit. I was quite pleased with parts of our game. We tried to squeeze them. If they peppered us on our 18-yard line they'd have scored quite a lot so we tried to keep them out of our box."

Celtic manager Ange Postecoglou: "The pitch was one of the obstacles. As the game wore on, it just got more and more hard for the lads to get a foothold. We controlled the game really well early on.

"We scored a couple of good goals, some great movement. Disappointed we conceded but again great reaction from the lads to go up the other end and get a third."

What's next?

Celtic return to Scottish Cup competition with a home tie against St Mirren on Saturday (17:30 GMT) as their silverware pursuit on three fronts moves forward.

St Johnstone have a 13-day break before travelling to Dundee United (15:00) in what will be a crucial contest in the context of their Premiership season.

Line-ups

St Johnstone

Formation 5-4-1

1Matthews

14Wright2Brown5Mitchell4Considine3Gallacher

23Carey18MacPherson34Phillips26McLennan

7May

1Matthews14WrightSubstituted forWotherspoonat 69'minutes2BrownBooked at 89mins5Mitchell4ConsidineBooked at 90mins3Gallacher23CareySubstituted forBairat 84'minutes18MacPherson34PhillipsSubstituted forHallbergat 79'minutes26McLennanBooked at 78minsSubstituted forMurphyat 84'minutes7MaySubstituted forRuddenat 79'minutes

Substitutes

6Gordon10Wotherspoon11O'Halloran16Rudden17Bair20Sinclair21Crawford22Hallberg29Murphy

Celtic

Formation 4-3-3

1Hart

2Johnston20Carter-Vickers4Starfelt3Taylor

13Mooy42McGregor41Hatate

17Neves Filipe8Furuhashi38Maeda

1Hart2Johnston20Carter-Vickers4Starfelt3TaylorBooked at 72mins13MooySubstituted forTurnbullat 79'minutes42McGregor41HatateSubstituted forAbadaat 69'minutes17Neves FilipeBooked at 41minsSubstituted forHaksabanovicat 87'minutes8FuruhashiSubstituted forOhat 79'minutes38MaedaSubstituted forO'Rileyat 69'minutes

Substitutes

9Haksabanovic11Abada14Turnbull18Kobayashi19Oh24Iwata29Bain33O'Riley49ForrestReferee:David DickinsonAttendance:7,758

Live Text

Match ends, St. Johnstone 1, Celtic 4.

Second Half ends, St. Johnstone 1, Celtic 4.

Goal! St. Johnstone 1, Celtic 4. David Turnbull (Celtic) right footed shot from outside the box to the bottom left corner. Assisted by Matt O'Riley following a set piece situation.

Andrew Considine (St. Johnstone) is shown the red card.

Hyeon-Gyu Oh (Celtic) wins a free kick in the attacking half.

Foul by Andrew Considine (St. Johnstone).

James Brown (St. Johnstone) is shown the yellow card for a bad foul.

Sead Haksabanovic (Celtic) wins a free kick on the left wing.

Foul by James Brown (St. Johnstone).

Attempt missed. David Wotherspoon (St. Johnstone) left footed shot from the right side of the box is high and wide to the left. Assisted by James Brown.

Substitution, Celtic. Sead Haksabanovic replaces Jota.

Attempt missed. David Turnbull (Celtic) right footed shot from the centre of the box is close, but misses to the left. Assisted by Hyeon-Gyu Oh.

Attempt blocked. Jota (Celtic) left footed shot from the left side of the box is blocked. Assisted by Cameron Carter-Vickers.

Substitution, St. Johnstone. Jamie Murphy replaces Connor McLennan.

Substitution, St. Johnstone. Theo Bair replaces Graham Carey.

Attempt blocked. Matt O'Riley (Celtic) left footed shot from outside the box is blocked. Assisted by David Turnbull.

Corner, Celtic. Conceded by Alex Mitchell.

Offside, Celtic. Jota tries a through ball, but Matt O'Riley is caught offside.

Substitution, Celtic. David Turnbull replaces Aaron Mooy.

Substitution, Celtic. Hyeon-Gyu Oh replaces Kyogo Furuhashi.

Player of the match

FuruhashiKyogo Furuhashi