Manchester United and Manchester City could both get knocked out of the Champions League on Wednesday while French champions Lille will also endure a nerve-wracking 90 minutes.
Three-times winners United, who have injury problems, need a draw at FC Basel to progress with Benfica from Group C and could still snatch top spot if they better the Portuguese side's result at home to bottom team Otelul Galati.
Premier League leaders City have a much tougher task of making the first knockout round on their Champions League debut.
Roberto Mancini's team must beat Group A winners Bayern Munich at home and hope eliminated Villarreal do them a favour and take at least a point in Spain against Napoli.
Lille have to defeat rivals Trabzonspor at home to qualify while the Turks, who are only in the Champions League because compatriots Fenerbahce were kicked out, know a victory would put them through.
Inter Milan have already won Group B and CSKA Moscow, who travel to the 2010 winners, still have a chance of joining them in the last 16 if they win and the Lille game is drawn.
Ajax Amsterdam need a point at Group D winners Real Madrid to guarantee reaching the knockout phase but even if they lose Olympique Lyon must thrash whipping boys Dinamo Zagreb and overturn a goal difference of seven to deny the Dutch side.