CELTIC swept aside St Mirren this afternoon to maintain their five point lead at the top of the Scottish Premiership.

The 2-1 result was the perfect preparation ahead of Sunday's crunch derby day at Parkhead against Rangers. Callum McGregor opened the scoring from an Odsonne Edouard pass before James Forrest doubled the Hoops' lead after clever play, again, from Edouard before Cammy MacPherson's late free-kick flattered Saints who offered little.

Here's five things we learned from Celtic's win in Paisley.

Kris Ajer should score more goals

The Norwegian defender won every ball inside the opposition penalty area in the first 20 minutes or so yesterday. That he failed to hit the target with any of his opportunities is an issue he will surely be kicking himself over.

For the centre-half to find such space and time inside the box is clearly a testament to the work done on Celtic's training pitch day-in, day-out. But he really should do a lot better with his end product. Two goals in 38 appearances this season in all competitions for Ajer is not a great return. 

He could have had at least one more in the first half at the Simple Digital Arena and will be frustrated on a personal level not to net - even if he was bailed out by his free-scoring teammates.

Saints should be just fine

St Mirren's season will not be defined by games against Celtic. But what can be said is that if they apply themselves against their closest rivals as they did in some aspects of yesterday's clash, they'll be okay.

Saints found some success when they hassled and harried Celtic early doors.

They have some talented players in their ranks, the likes of Ilkay Durmus, Junior Morias and Kyle Magennis to name a few.

Spirit alone may not win games of football, but if Jim Goodwin's team can marry their effort with some big goals at vital moments and a bit of luck, they'll be safe.

Edouard gives more than goals

Celtic's French striker may not have added to his own scoring tally in this one but his contribution was still match-winning. Two invaluable assists to provide goals for McGregor and Forrest helped seal the points for his side.

It may not have been a match with dozens of opportunities for the striker himself, but that's the mark of a top player.

His influence on proceedings was clear for all to see and the fact that he was brought off with 10 minutes to play showed that Neil Lennon needs his standout star fit for Sunday's Rangers clash.

Harmful high-press?

Celtic weren't tested too much by St Mirren but they did show some discomfort against Jim Goodwin's intense set-up.

The Irishman had his players swarming the Champions early on, which didn't seem to suit defenders Ajer and Christopher Jullien too well.

Boli Bolingoli was another who seemed to find it tough getting the ball out from under his feet when harried by two Saints bodies - which could be a sign of what teams must do to take anything from the Hoops.

Rangers won last season with a similar set-up and would be forgiven for setting up the same way again.

Prepared Celts

With any Old Firm derby around the corner, all Celtic and Rangers can hope for in their build-up is momentum-building victories.

Celts didn't have to get out of second gear to gain three points which will have satisfied their manager.

Their big players performed, they were able to substitute and successfully rest James Forrest and Odsonne Edouard and they head into Sunday's powderkeg game with as fresh a squad as possible with a five point lead.