WITH the third Old Firm fixture of the season on the horizon, fans of both sides of the derby will be feeling optimistic about their chances of securing bragging rights in Glasgow. Celtic will surely be the bookies’ favourites to pick up three points, but Rangers fans will be quietly confident that they can leave Celtic Park as the victors.

While Steven Gerrard’s side won the previous Old Firm, winning at Celtic Park provides a more difficult challenge for the Ibrox club and Rangers supporters will be hopeful that top scorer Alfredo Morelos can finally break his derby duck and inspire his team to victory.

Morelos’ case is a curious one, as the Colombian is yet to find the net against Celtic in his previous seven outings against the Scottish champions. Celtic supporters are quick to bring this up whenever Morelos is praised by his own fans and point to this as evidence that the 22-year-old isn’t all he is cracked up to be.

The Rangers striker is clearly a forward who shows a lot of promise - Colombian superstar James Rodriguez said as much after Morlelos played last week for the national side - but the argument made by Celtic fans is not without merit: why has Morelos not scored in the Old Firm?

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The graphic above details Morelos’ expected goals (xG) in the seven Old Firm derbies he has played in since moving to Ibrox, and the numbers certainly suggest that Morelos should have got on the scoresheet at some point or another. There have been games where he’s struggled to get on the end of clear goalscoring opportunities - Celtic’s 1-0 win at the start of the season comes to mind, as does Rangers’ win at Ibrox in December - but then there are others where the Rangers top scorer has simply fluffed his lines.

Cumulatively, Morelos has an xG of 2.91 over the seven Old Firm games he has featured in, implying that he should really have scored on at least three occasions in Glasgow’s tempestuous derby. Rangers’ 0-0 draw at Parkhead last season under Graeme Murty is the most clear example here; Morelos scored an xG of 0.83, yet failed to find the back of the net.

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There is a noticeable drop-off in Morelos’ stats every time he plays Celtic, suggesting that for some reason or another, Morelos is never quite firing on all cylinders during the biggest games of Rangers’ season. The 22-year-old’s xG per 90 minutes drops - implying that he is unable to get on the end of as many chances as he usually does - as does the number of shots he attempts, and their accuracy. In short: Morelos doesn’t play as well in these games, going by the most important metrics for any striker.

This is indicative of a wider issue with Morelos. There is no question that the Rangers striker is one of the most effective forwards in the country, but the goals have a tendency to dry up in Rangers’ biggest games. Critics of this position will rightly point out that Morelos bagged four goals in European football this season - not a bad haul, by any means - but Morelos does have form for failing to find the net in Rangers’ biggest fixtures.

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Morelos’ record against the better teams in Scotland and in Europe has not matched his goalscoring exploits against lesser teams, although it should be pointed out that the young forward is improving in this regard. Last season, Morelos scored just three goals in 17 league games against teams that finished in the top six, and failed to register a goal during his sole outing in the Europa League against Progres Niedercorn.

This year, Morelos scored four goals in 14 European appearances for Rangers, a rate of 0.29 per 90 minutes. For a point of reference, Morelos’ goals per 90 for his entire time at Ibrox stands at 0.55: nearly double his strike rate in Europe. Against this season’s top six the Colombian is performing better than he did last season, although some improvement is still required if Morelos is to develop into a big-game player.

Morelos has found the net seven times in 13 league appearances against the Premiership’s top six this season; certainly a step in the right direction for the striker, but the fact remains that he still isn’t influencing big games for Rangers in the same manner he does against weaker opposition. Since joining Rangers, Morelos has made 46 appearances against the league’s top six and in Europe, and has just 14 goals: a strike rate of just under one in three.

So why is this happening? Why is a player who has scored 29 goals in all competitions this season struggling in the bigger games? The answer could well be with Morelos’ mentality. At least, that’s what sport psychologist Tom Lucas thinks.

HeraldScotland:

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"The issue grows exponentially the longer it goes on. A small problem for Morelos can suddenly become a big problem because he hasn't scored and maybe he's trying too hard," said Lucas.

"His natural instinct maybe deserts him at the crucial time and he stiffens up. Once you do that, you're not in control of your muscles because you're really trying too hard. That's why Morelos misses these chances.

"The trouble is that when players have too much time to think about it, your natural instinct maybe takes you one way or another. But when you're suffering, when you think 'Oh God I missed the last one', your attention span is gone. And the result is that in that moment, you lose control.

"So Morelos has got to get himself back into thinking 'I've done this before, I'll score this time'. He's now on the negative side thinking 'I'm going to miss again'. So he's allowing that thought process to become the main thought process, instead of dismissing it and looking at how he's going to finish it, rather than 'I didn't finish it the last time'."