FANS of both halves of the Old Firm have always argued about which of their players would get into the other’s team. Barring the most blinkered supporters, most accept that there isn’t one team who are better in every area of the pitch and are able to concede that some players would be able to fit in to the starting XI at the other side of Glasgow.

Earlier in the week, we took a look at the difference in the numbers that Rangers and Celtic have been posting this season in an attempt to highlight the gap between the two sides at present. While Celtic are the better side at present, statistically speaking, there are still areas of the pitch where Rangers players are outperforming their rivals. To that end, we’ve decided to create a mixed Old Firm XI. Would you rather have Alfredo Morelos or Odsonne Edouard up front? Scott Bain or Allan McGregor in goal? Scott Sinclair or Ryan Kent?

We’ve delved into this season’s numbers in an attempt to settle the debate and come up with a combined Old Firm XI based on the statistical evidence available. We’re going to go with a 4-2-3-1 formation, given that both Celtic and Rangers regularly line up in this manner.

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Let’s start at the back. Rangers’ acquisition of Allan McGregor in the summer has been a fine bit of business on behalf of the Ibrox club, particularly given the 37-year-old’s performances in Europe. For Celtic, Scott Bain has been given an extended run in the first team and has excelled of late.

Bain has the edge over McGregor and Craig Gordon this season, going by the numbers. McGregor has a positive discrepancy between his goals conceded and expected goals against (xGA) of 0.08, which means he is currently conceding fewer goals than he reasonably should. Gordon is conceding exactly as many as he should be, while Bain is performing fantastically at the moment, preventing 0.36 goals per 90 minutes that he reasonably not ought to be. For this reason, Bain will be our man between the sticks.

As the table above demonstrates, Kieran Tierney is a shoo-in at left back in our combined XI. Tierney wins slightly fewer defensive duels than Borna Barisic on average, but has a greater interception rate and attempts far more balls into the final third - a crucial aspect of the role of a modern full back.

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It’s not quite as clear-cut at right back. Mikael Lustig wins more defensive duels than James Tavernier, but the Rangers captain makes significantly more interceptions over the course of any given match. Celtic’s Swedish right back makes more passes forward - and with a higher success rate - but doesn’t average as many assists. Due to his attacking output, we’re going to select Tavernier at right back.

The table above highlights the most important statistics for each centre back to have featured regularly for Rangers and Celtic this season, and there can be little doubt that Brendan Rodgers’ players have the edge here. Every Celtic centre back wins more defensive duels than their Rangers counterparts, almost all of them are more effective with dealing with aerial balls into the defence and all have significantly better passing stats.

We’ve opted for Filip Benkovic - hardly surprising, given the fact that the on-loan defender is probably the highest-performing centre back in the league this season - and his team-mate Dedryck Boyata. The Belgian international isn’t as dominant in the air as others here, but his excellent ball distribution and impressive success rate at defensive duels put him slightly ahead of the other options.

There are two spots available at the base of our midfield, and no shortage of players to potentially slot in here. For the purpose of this analysis we’ve included Callum McGregor as a central midfielder, as opposed to an attacking one, given the amount of time McGregor has featured here for Celtic over the course of the season.

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Celtic captain Scott Brown is the outstanding performer here, even if his abilities have been on the wane this season. No other midfielder from those in our list makes as many interceptions, no-one makes as many passes and no one does so with a greater degree of accuracy. Brown’s an easy pick.

Choosing his partner in our combined XI isn’t quite as straightforward, but we’re opting for Rangers’ Ryan Jack. Only Brown makes more interceptions than Jack, and his success at winning midfield duels is only bettered by his team-mate Andy Halliday. McGregor does hit more passes than Jack admittedly, and with a slightly higher degree of accuracy, but on balance Jack gets the nod ahead of him.

Both Celtic and Rangers have a number of wingers at their disposal and as the graphic above demonstrates, choosing two isn’t particularly easy. James Forrest is a fairly obvious choice on the right; the 27-year-old dribbles around three times as much as his Ibrox counterpart Daniel Candeias, does so more successfully, sets up more goals and scores more himself.

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On the left, there is a bit more room for debate. No Old Firm winger dribbles as much as Ryan Kent, and only Glenn Middleton averages more shot assists over 90 minutes. Scott Sinclair’s goal rate is significantly higher than Kent’s here, but aside from that the English winger finds himself second-best to Kent in most regards. We’re selecting Kent on the left because of this.

We need one more player for our midfield, a playmaker to fill in in the number 10 role just behind the striker. There are three players who have played regularly here for Celtic and Rangers this season: Scott Arfield, Ryan Christie and Tom Rogic.

The above table highlights each playmaker’s stats so far this season, and it looks like Ryan Christie is outperforming his peers by these metrics. Christie manages marginally more passes into the final third than Arfield, and with a greater degree of accuracy, too. While Rogic and Arfield are tied on a goals per 90 minutes of 0.23, Christie has an impressive ratio of 0.37 goals per 90. This ability to find the net, combined with the midfielder’s eye for a pass, means Christie is our pick to play attacking midfield.

All that’s left now is to pick a striker. The graphic above highlights each striker’s shots per 90 minutes, their accuracy, their goals per 90 and expected goals (xG) per 90 minutes. Once again, there’s a marginal decision to be made going by the numbers, but we’re going for Alfredo Morelos.

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The Colombian has a marginally higher goals per 90 than Odsonne Edouard, although Celtic’s French striker hits more of his shots on target. Interestingly, the difference between the two players’ goals scored and xG - the primary indicator of whether or not a striker is overperforming - is exactly the same, with both forwards scoring 0.11 more goals per 90 minutes than they reasonably should be. But the fact that Morelos is the Premiership’s top scorer cannot go unnoticed and with the differences between the two players so slim, this is our deciding factor in selecting the Rangers forward.

So there you have it. There will be fans of both Celtic and Rangers that will no doubt disagree vehemently with our combined XI; if you do, let us know in the comments who you think deserves a place in our Old Firm XI.