A bemused Jose Mourinho was left counting the cost of a first Champions League defeat of the season after Manchester United lost to a late goal in Basle on Wednesday night.
Michael Lang's 89th-minute winner means that United, Basle and CSKA Moscow can all finish on 12 points in Group A if the Russians win at Old Trafford next month.
However, CSKA would have to beat United by six goals, meaning that Mourinho's side are almost certain to progress to the knockout stage despite losing their 100 per cent record.
'Can you help me with the maths?