One day in the distant future Celtic supporters will come to appreciate the player they had in James Forrest.

Despite his 17 trophies eclipsing half the Lisbon Lions the Scotland winger remains a strangely under-appreciated figure. There are no songs in his honour. No statues on Celtic Way.

Hours after signing a new four year contract tying him to the club until 2023, however, the 28-year-old proved he's the real deal with the decisive goal in the stodgy win which kept Celtic top of the SPFL Premiership.

For 49 minutes St Mirren did their jobs superbly. They chased, harried, blocked and frustrated.

Their resistence was finally broken down when Odsonne Edouard's shot careered off the upright and Mohammed Elyounoussi tapped in his sixth goal in six games.

Any prospect of Rangers returning to the summit of the SPFL ended when Forrest marked his new deal with his tenth goal of the season four minutes later, adding a sponsors' man of the match award for his efforts

It was a significant night, too, for Greg Taylor. The £2.2million signing from Kilmarnock was rarely tested in a defensive sense by a St Mirren side focussed on giving nothing away. Nevertheless, the Scotland defender had a fine game.

The only concern for Neil Lennon came in 69 minutes with the rare sight of captain Scott Brown limping from the field gingerly. By then the game was pretty much won.

Celtic's matchday announcer read out the teams before kick-off dressed as the Grim Reaper and St Mirren really didn't need any further harbingers of doom here.

The Paisley side arrived in the east end of Glasgow on the back of 12 straight defeats since a 1-1 draw in December 2007. Without a win in 23 visits, their last victory was in April 1990, almost three decades ago,

In each of their last three visits to Parkhead the Buddies had lost four goals, arriving on the back of five straight away defeats.

It came as no surprise, then, to see Jim Goodwin's side line up with eleven men behind the ball, organised and drilled to within an inch of their lives. The challenge for Celtic was breaking them down. In stark contrast with Sunday in Aberdeen it took time and patience, St Mirren closing down the space in a dogged first half display.

How different things might have been had Callum McGregor taken a chance after creating space in the area in the second minute. As so often against Celtic the impressive Saints keeper Vaclav Hladky produced a fine save. It wouldn't be his last.

The home support settled back in expectation of more chances and inevitable goals. It didn't quite turn out that way. With nothing on Ryan Christie tried an optimistic dipping 20 yard drive seen narrowly over the bar by Hladky in 17 minutes.

The late hero from a corner kick against Lazio last week Christopher Jullien had two outstanding chances to repeat his heroics from Ryan Christie corners. He made his run a fraction too soon for the first, heading a glorious chance over the bar with the goal gaping.

Nine minutes from half-time he had another go with a downward header, his effort blocked on the line. Celtic's best effort of the opening 45 minutes came shortly before half-time, when James Forrest came closest to celebrating his new deal with a goal.

Finding a rare yard of space behind Callum Waters the winger thrashed a fizzing, rising right foot shot at goal. Once again Hladky denied the home side, touching the ball onto the upright. Forrest had no reason to worry, the goal was coming. Yet as the first half ended St Mirren could be satisfied with their discipline and concentration.

Quick and alert on the break, the visitors showed limited menace threatened in attack just once. In 24 minutes Jon Obika plucked a high ball out of the air. One on one with Jullien he held off the Celtic defender and managed a low shot on goal. Fraser Forster gathering comfortably.

As the half-time whistles rang out around the country Rangers were heading back to the top top of the league with an improved goal difference. Celtic had 45 minutes to retain their place at the summit.

In the event they needed only four. Amongst the many aspects of the first half which must have pleased Jim Goodwin was the invisibility of Odsonne Edouard. It couldn't last forever.

Just as the second period threatened to fall into the same pattern as the first - Celtic probing, St Mirren forming a Mexican wall - the Frenchman burst into life. Gathering a Scott Brown pass on the edge of the area the intention was clear from the start. For once St Mirren's defence stood off just enough for the top scorer to crack a shot off the inside of the post.

Briefly, it seemed as if the visiting goal would continue to live a charmed existence until Mohammed Elyounoussi tapped in from close range. Almost unnoticed the Norwegian loan signing has emerged as a consistent scorer of goals. Few were as welcome as this one. The sigh of relief around Celtic Park was audible.

The gates finally prised open, the home team began to relax and play. They doubled their lead after 54 minutes. Given the events of the day there was an inevitability to Forrest finally claiming his goal.

It was a simple affair, the Scotland international gathering on the right side of the area and cutting onto his left foot to drive a low shot into the net through a ruck of legs.

Now and then comes a reminder that Edouard is as fallible as the rest of us. As Jim Goodwin pushed Tony Andreu on to broaden St Mirren's attacking horizons, Celtic had the rare luxury of a swift counter attack after 66 minutes. James Forrest gathered a raking long ball on the right flank and took his time before squaring for Edouard to blaze the ball over the crossbar from 12 yards. Around Celtic Park supporters rubbed their eyes.

Edouard made way for Lewis Morgan with eight minutes to play, debutant Greg Taylor receiving a warm and deserved round of applause as he made way for Jonny Hayes in the final moments. The former Kilmarnock left-back's first start looks unlikely to be his last.