“OUR back four has had no continuity, that’s always part of conceding goals.”

Karl Robinson said those words last month, but they could easily have come after Saturday’s win over Shrewsbury Town.

The Oxford United head coach deployed his 17th different defensive combination of the Sky Bet League One season at Montgomery Waters Meadow as Luke McNally, John Mousinho and Steve Seddon lined-up in a back three.

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That gives an insight into how much Robinson has had to rotate - and the statistics support his claim.

Since starting with a back four of Anthony Forde, Elliott Moore, Jordan Thorniley and Steve Seddon at Cambridge United on the opening day of the campaign, the U’s have named an unchanged defence just 14 times in League One.

They kept a clean sheet in five of those games, which is a shutout rate of 36 per cent.

That falls to 13 per cent when Robinson has changed his defence, with just three clean sheets in 23 matches.

Those came in the stalemate against Wycombe Wanderers in September, the 3-0 win over AFC Wimbledon in December and last month’s 4-0 thrashing of Charlton Athletic.

United also let in fewer goals when they field an unchanged back line, with 14 conceded in 14 games.

When they have rotated they have shipped 33 in 23 matches.

It means the U's have only once named an unchanged defence for more than two games in a row and that came earlier in the season.

They started with a back four of Sam Long, Moore, Thorniley and Seddon for six successive matches between the 2-1 win at Sheffield Wednesday on October 2 and stalemate at Ipswich Town on November 13.

The U’s conceded six times in those six games and claimed two of their eight clean sheets this season.

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It perhaps helps explain why fourth-placed United only have the joint tenth-best defensive record in League One.

Their record of eight clean sheets is also only 16th in the division, with all of their promotion rivals at the top of that particular table.

Of course, there are other factors, with Alex Gorrin’s long-term injury depriving the U’s of a specialist holding midfielder and more stability in that position.

United’s front-foot style will inevitably leave them vulnerable defensively and they have been hit on the counter-attack several times in recent weeks.

But the enforced rotation clearly does not help and the U’s will hope for more continuity in the final eight matches of the season.