Only a collapse of epic proportions can stop Manchester City from reaching the quarter-finals of the Champions League on Wednesday, but Pep Guardiola still feels it is necessary to warn his players about the fine margins at this level just in case.
City have a four-goal lead and home advantage against Swiss underdogs Basle, suggesting the second leg of their last-16 tie at the Etihad will be little more than a formality.
However, Guardiola is wary of the threat that red cards could pose to his team's progress, both on Wednesday night and in the final stages of the competition.