THE transfer window has only been open for just over a week, but Scotland’s top sides have wasted no time in bringing new bodies in and getting deals over the line.

With Celtic and Rangers only separated by goal difference at the Premiership’s summit - albeit with the Ibrox club having played an extra game - both halves of the Old Firm are desperate to bring in reinforcements to help swing the title race in their favour.

Celtic have already brought in Oliver Burke and Timothy Weah on loan and are seriously interested in Ivorian striker Vakoun Issouf Bayo.

STEVEN GERRARD: Write off a silverware-hungry Jermain Defoe at your peril

At the other side of Glasgow, Rangers have signed Kilmarnock’s Jordan Jones and Dundee’s Glen Kamara on pre-contracts and have brought in Steven Davis and Jermain Defoe to help with their title tilt this season.

Defoe’s move has been arguably the most eye-catching signing in the Premiership so far in January and has sparked debate over whether or not the 36-year-old still has what it takes to compete at this level.

We’ve decided to take a look at the Englishman’s stats to see exactly what Rangers fans can expect from their new man.

Defoe has always been seen as a natural goalscorer and with 163 goals in the English Premier League it’s not hard to see why. The ex-Spurs striker is the seventh-highest goalscorer in the competition’s history and has spent almost the entirety of his career in England’s top flight.

The graphic above charts Defoe’s goals per 90 minutes in league football since the 2001/02 season and the results make for impressive reading. Even during the forward’s worst season in front of goal, in 2010/11, he was still averaging 0.24 goals per 90 mins, or around a goal every four games if you’d prefer. This is hardly prolific, of course, but it isn’t a poor return in such a demanding league.

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Perhaps unsurprisingly, Defoe’s best goalscoring campaign came in the 2013/14 season when he was playing for MLS side Toronto but of the 16 seasons he’s spent in England’s top flight, Defoe has averaged more than a goal every two games on seven occasions. Even as recently as 2015/16, the forward was scoring 0.53 goals per 90 - a figure not to be sniffed at.

By analysing Defoe’s scoring rate over the last 17 seasons, we can see that there are peaks and troughs but - much to the encouragement of Rangers fans - there is no sustained period of clear decline. Yes, Defoe’s goalscoring rate has dropped in the last two seasons but there are a couple of mitigating factors here. Firstly, that during 2016/17 Defoe was tasked with banging in the goals for a truly dreadful Sunderland side that looked destined for relegation from the opening day. And secondly, that last season at Bournemouth he was a bit-part player, often coming off the bench and rarely given a run in Eddie Howe’s starting XI.

If we take Defoe’s average goals per 90 minutes over the last three seasons as a representative sample, the figure we arrive at is 0.42. It’s important to point out that these are goals scored in the English Premier League, where the standard is higher than the Scottish Premiership, yet even going by these numbers it appears Defoe will have plenty to offer to Rangers during his time at Ibrox.

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Comparing this scoring rate against players that have played a minimum of 600 league minutes this season, it looks as if Defoe will be able to more than hold his own in Scottish football. Defoe ranks at joint-tenth place, tied with Celtic’s Scott Sinclair and his new team-mate Kyle Lafferty. It’s probably fair to assume that Defoe will fare better against Premiership opposition too, given the gap in quality between the two league’s, but even going by these numbers he should be able to make an effective impact this season.

A more in-depth look at Defoe’s numbers reveals that the veteran striker’s role has been changing in recent seasons. Where Defoe has traditionally been characterised as a goalscorer, we can see that as age catches up with the 36-year-old, his style of play has evolved.

We can see that Defoe’s goalscoring has dropped significantly - particularly last season when he wasn’t featuring regularly for Bournemouth - but other aspects of his game have actually improved in recent campaigns. While the English forward is scoring fewer goals and hitting fewer shots, his accuracy has increased to the point where the majority of his efforts on goal are on target.

Interestingly, Defoe’s expected goals (xG) has remained fairly consistent during this time, implying that he’s still being given the same number and quality of goalscoring opportunities during any given match, but he’s converting fewer of them. This may be slightly worrying for Rangers supporters, but they can take heart from the fact that Defoe’s team play has improved over the same period. The number of key passes - passes that lead directly to a shot - that Defoe averages more than doubled last season and the number of touches that he’s taking in the opposition box has also risen.

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Defoe’s dribbling has suffered at the same time, however, with the number of attempted dribbles per 90 minutes dropping from 3.44 to 2.1 and with good reason; in 2015/16, around 76% of the forward’s dribbles were successful, but that figure plummeted to 58% last season.

All in all, then, it looks as though Defoe still has plenty to offer and should prove to be an important player for Rangers during the second half of the season. Gerrard has already asserted that Defoe is “a very young 36-year-old” and that the striker “has a shape to die for in terms of how he looks after himself” in response to questions about age creeping up on the forward. The stats suggest that, naturally for a player Defoe’s age, there has been a drop-off in some aspects of his game, but his goalscoring record throughout his career suggests that he won’t struggle to find the net this season. Whether or not Defoe has what it takes to make it in Scotland remains to be seen but there are plenty of reasons for the Rangers support to be optimistic about his arrival.

This article originally appeared on the site of our sister title, The Herald