Barcelona fans are bound to be concerned by their team’s dreadful defensive start to the season, but they don’t need to get too worried just yet.

Conceding four goals in both of the first two competitive games of the season for the first time since 1950 looks terrible, true, but the extenuating circumstances should be taken into account.

Firstly, they are clearly still mentally in pre-season mode, with several players – including Lionel Messi and Dani Alves – only two weeks into their preparations after being given an extended break following the Copa America.

Secondly, the shocking collapse against Athletic Bilbao on Friday came just three days after a gruelling UEFA Super Cup against Sevilla in Georgia – 3,500km away – which went to 120 minutes and finished at 01:30 local time.

It’s not just a coincidence, surely, Sevilla also fared badly in their next outing, conceding six goals in a friendly against Roma on Friday.

Most significant, however, is the fact that individual errors have been largely responsible for their defensive problems, with six of the eight goals they conceded this week resulting directly from a mistake.

Various players have been culpable, with Jeremy Mathieu, Marc Bartra, Marc-Andre ter Stegen and Alves among those to blame, suggesting a collective lack of concentration.

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It certainly hasn’t been the case that Barca have been repeatedly sliced open by rampant opposition attacks.

If you studied the general pattern of play in the two games against Sevilla and Athletic without taking individual phases of action into account, there is no way you would conclude they had resulted in eight goals being conceded.

In terms of controlling games, Barca have been largely fine – but individual errors have let them down.

That doesn’t mean everything is OK. There is a real risk last season’s treble-winning exploits could result in the kind of complacency, leading to sloppy mistakes, which derailed Real Madrid midway through last season.

Luis Enrique should guard against that by reminding his players not to forget to keep doing the things which made them successful in the first place. If they regain last season’s discipline and focus, they will be fine.