FORGET the 90 minutes on Saturday. It will be the 31 days of January that will deliver clarity on the possibility of a genuine title race between Celtic and Rangers this season.

The build-up to next weekend’s derby at Ibrox will be as frenzied as ever. Rangers will feel they are in good shape to land a first league win over their rivals since March 2012. It would be a sizeable achievement but shouldn’t be considered a huge shock. Rangers have proved they can stay the distance so far this season, while Celtic have been vulnerable at times on the road, losing at Hearts, Kilmarnock and Hibernian. If Rangers play well, then a win shouldn’t be beyond them.

That would start the New Year celebrations early around Ibrox as the Premiership heads into the winter break, and spark talk of a proper championship challenge for the first time in years.

Steven Gerrard won’t be getting carried away if that comes to pass, however, and the more measured among the Rangers support will be similarly cautious. For while there may not be many games played in January, it will be the business done by both clubs during the transfer window that will shape the second half of the season.

On that front, Celtic continue to hold the upper hand. Brendan Rodgers did not hide his disappointment with the business done (or not done) by his club in the summer, most notably the failure to sign John McGinn and the subsequent departure of Moussa Dembele to Lyon on the last day of the window. He surely won’t be left frustrated for a second time.

Celtic have the financial might to blow the rest of Scottish football out of the water. With Rangers, as well as Kilmarnock and Aberdeen, still on their tails at the halfway stage of the season, they will surely not be reluctant to deploy that spending power. It could make all the difference.

It is not too difficult to ascertain just what Celtic need; strikers, and as many as you can spare. With Leigh Griffiths taking an indefinite break as he addresses personal issues, and Odsonne Edouard a short-term injury absentee, Celtic are woefully light in forward options.

Rodgers had said prior to Edouard’s injury he would require two centre forwards in January and may now be considering a third. Another right-back would be prudent, too.

January is a notoriously difficult month to bring in specific targets –and an element of panic buying undoubtedly creeps in towards the end – but Celtic must find a way to strengthen, even if it means attracting loan signings or paying more than they would wish. A last-32 Europa League tie against Valencia and the chance of an unprecedented third treble in a succession should provide all the motivation they need. If Celtic spend as they ought to, then an eighth successive title will be theirs in May.

Rangers need players, too, but don’t have the resources to compete with Celtic. Like their rivals, they will look to add reinforcements in the forward areas. Alfredo Morelos remains an enigmatic figure but without his goals Rangers would not still be within touching distance of Celtic.

Gerrard has said he would fall out with anyone at Ibrox if they tried to move the Colombian on in January, and it is a fight certainly worth having. No other Rangers player has reached double figures this season, while all-but-one of James Tavernier’s nine goals have been penalties. Morelos clearly needs help and Gerrard will try to get him it. Without Celtic’s financial might, the manager may need to lean on his contacts down south to try to unearth a striker who could make a difference, even if only on loan.

Rangers’ prospects, however, remain tied to Celtic. Should the Parkhead club strengthen as the manager hopes, then they should gradually move away from the pack in the second half of the season to win the title by a comfortable margin. But if Celtic fail to land the players they are after for whatever reason and Rangers are more successful in their recruitment, then it should make for an intriguing finale. All bets are off in that scenario.

THERE will be no such subtle tinkering at the other end of the table. St Mirren, desperate to try to move away from the bottom end of the Premiership, have been committed for some time now to completely overhauling their squad next month.

Scarred by the short but damaging tenure of former manager Alan Stubbs, his successor Oran Kearney wants to both reduce the size of his bloated playing roster while also bringing in signings he feels will add the quality he so badly needs. That could see as many as a dozen players moving on, and perhaps five or six coming in. It has a real roll-the-dice feel to it.

St Mirren pulled off a similar stunt two years ago when they sat bottom of the Championship, letting 10 move on and replacing them with 10 new faces. That eventually had the desired effect and they escaped relegation on the final day. Now playing in a division higher, they need both a better calibre of signing plus somehow persuade players on multi-year deals to move on, or pay them up. It could be a costly exercise but they may have no alternative.