JAMES Forrest produced a signature finish to seal another three priceless Premiership points on the day he put pen to paper on the contract extension which will see him commit the best years of his career to Celtic. The 28-year-old wandered in off the left to fire in a low finish through a ruck of players for the goal which took this match away from a well-organised St Mirren side, just seconds after Mohamed Elyounoussi had opened the scoring. But what else did we learn from a night where Celtic came good in the second period to stay top of the table on goal difference after the Paisley side had given them a pre-Hallowe’en first half scare?

STUBBORN ST MIRREN

It isn’t yet November but these are the nervy nights where titles are won and lost. A full midweek card with both Celtic and Rangers kicking off at the same time for once, on paper, Rangers’ trip to Dingwall appeared the most arduous of the two Old Firm assignments. But Jim Goodwin, a former Celtic youth player when Neil Lennon was running the show in midfield, had different ideas. He was determined to put a spoke in the wheels of a smoothly-running Parkhead machine which had racked up ten goals in their last two league outings. They can take pride in the way they marshalled themselves in the first half here, defending calmly and deep, with Jonathan Obika leading the line intelligently even in battles against the excellent Christopher Jullien. While they plugged away gamely even in the second period, two goals in the first ten minutes of the half killed them. They deserved a better fate than to finish the night rock bottom of the division.

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FORREST ON FIRE

It was somehow inevitable that Forrest would produce something to celebrate his new contract. With the crowd converting their old Brendan Rodgers chant about “being here for ten in a row” in his honour, this was nothing special here, just the wee man doing what he does best. This was his tenth of another prolific season, another bottle of man of the match champagne to go with it.

St Mirren were still reeling from the loss of Elyounoussi’s opener when this stocky little winger showed everything he has brought to his game over a remarkable trophy-laden stint at the club. Fed the ball quickly by Callum McGregor, he had St Mirren left back Callum Waters backing off then fired in a low effort with his left foot which flew through a ruck of players into the bottom corner. Minutes before half time, he had also produced Celtic’s best chance of the first half, a stinging drive from an angle which Hladky touched onto a post.

SCOTT BROWN INJURY SCARE

This match already seemed won when Scott Brown pulled up on the edge of the St Mirren penalty area, looked forlornly over at the bench and passed on his captain’s armband to Callum McGregor. While it didn’t look as though the 32-year-old was in any huge pain, it seemed likely to be a muscle pull and if so that would make him almost certainly out of Sunday’s BetFred Cup semi-final against his former team Hibernian on Saturday. While Celtic go into that match as huge favourites against Paul Heckingbottom’s beleaguered squad, and Olivier Ntcham is a ready-made replacement – just as he was here - the club’s talisman is a big match player and his loss will be noticed.

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FULL BACK FLUX

One of the perils of having a big squad is having to keep everyone happy. And one of the perils of the emergence of Jeremie Frimpong is the difficulty of trying to feed the mouths behind him in the pecking order.

As blown as away as he has been by the teenage Dutchman’s displays against Ross County and Aberdeen in the last week or so, Neil Lennon decided yesterday that it was time to leave him out of the match squad. With Hatem Elhamed likely to return against both Hibs and Lazio, that meant restoring Moritz Bauer against St Mirren but the Austrian – who perhaps now finds himself third choice right back at the club - seemed more than a little rusty here.

On the other flank, it has been a frustrating wait for Celtic’s big deadline day signing. But finally, exactly two months into his Celtic career, there was a debut for Scotland left back Greg Taylor. He spent most of the match on the edge of the St Mirren penalty box and might have had an assist had there been any takers in the six-yard box when his low cross from the left at the end of the first half zipped past the dive of Vaclav Hladky. All in all, Taylor did fine here, earning an ovation before he departed the fray late on to make way for Jonny Hayes.

STRIKER SHORTAGE

The two-goal lead allowed Odsonne Edouard to rest up for challenges of Hibs and Lazio to come, rather handily because he is currently the only fully-fit first team striker at the club. While St Mirren’s defenders kept him in check well yesterday, the Frenchman still produced the moment of quality which opened this game up. Those quick feet of his worked the yard he needed to fire in the strike from the edge of the box which beat Vaclav Hladky, the rebound knocked gleefully into the empty net by Elyounoussi after Christie’s attempt had deflected off Waters. With Leigh Griffiths expected back in training today, and Vakoun Bayo's status is unclear, Lewis Morgan was given his chance to deputise late on but Celtic couldn’t add to their tally.