Rangers are battling to avoid Brendan Rodgers bringing up a first Celtic 10-in-a-row when the sides meet in Sunday’s Scottish Cup semi-final.
Celtic have never had a 10-game unbeaten run across the country’s three major competitions in facing up to an Ibrox opponent.
Indeed, there has never been such a 10 in the Premier era that began in 1975-76 and ushered in four league meetings a season.
Between 1995 and 1997, Walter Smith’s Rangers contested nine straight derbies without losing to their ancient adversaries - the best such sequence without defeat in the past four decades.
Rodgers’ side have the opportunity to eclipse that this weekend, with the Irishman unbeaten in the fixture across his 21 months in charge.
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His derby dominance is reflected by the fact that he boasts seven wins and two draws in the confrontation.
This run, which followed Rangers edging out Celtic courtesy of a penalty shoot-out in the 2016 Scottish Cup semi-final, comprises five wins and two draws in the league, and victories in the semi-finals of both the League Cup and Scottish Cup last season.
The longest unbeaten run in Scotland’s biggest derby was achieved by Rangers between 1960 and 1964. Then they clocked up a 14-game sequence in the fixture without loss.
Avoiding an unwanted 10 is not the only matter of historical importance resting on the outcome of Sunday’s Scottish Cup semi-final for Rangers.
Failure to upset the odds and prevent Celtic effectively moving to within one win of an unprecedented double treble would make for a seventh straight season that no major silverware would have headed Ibrox way.
This would equal the previous longest such barren spell, which came between 1903-04 and 1909-10.
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