Pep Guardiola acknowledges Manchester City have tightened up defensively in their last two games but claims anything could still happen at Hull on Boxing Day.
City emerged from a bad spell by keeping a first clean sheet in nine attempts in a victory over Watford earlier this month and followed up by coming from behind to beat Arsenal 2-1 last week.
The back line has appeared to be City's weak link this season but Guardiola has stressed the way to improve it is not by focusing on fundamentals such as tackling, but improving the all-round play of the team.