Arsenal host Bayern Munich while Real Madrid travel to Napoli
Arsenal are staring elimination at the hands of Bayern Munich in the face again when they welcome the German champions to the Emirates on Tuesday night.
Arsene Wenger's men were humbled 5-1 in Munich last time out and will all but certainly be knocked out when the sides meet in their second leg.
Arsenal are under pressure in the Premier League having lost three of their last four matches which included a 3-1 loss at rivals Liverpool at the weekend and have now dropped out of the top four postions.
Furthermore, Wenger has had to fend off suggestions that he fell out with star player Alexis Sanchez leading up to the Anfield clash and that was the real reason the Chilean didn't start the game.
Arsenal were dominated by Bayern in the first leg although they really fell apart after defender Laurent Koscielny was taken off just after half time.
No team has ever progressed in a Champions League tie after losing the first leg by four or more goals.
Bayern are seven points clear at the top of the Bundesliga and have only lost one league game all season and they've scored 11 goals in their last two matches.
The other game tonight sees holders Real Madrid head to Italy to take on Napoli. The Spanish giants hold a 3-1 advantage going into the tie but have looked vulnerable in recent weeks.
Zinedine Zidane's side went unbeaten for 40 matches earlier this year but their record run was finally stopped with two late goals at Sevilla in January.
Napoli's Lorenzo Insigne celebrates after scoring the opening goal against Real Madrid. Picture by: Daniel Ochoa de Olza/AP/Press Association Images
In recent weeks, they have lost 2-1 to Valencia, came from two goals down to beat Villareal and needed two late goals to draw with lowly Las Palmas in the Bernabeu - all of which has seen arch-rivals Barcelona overtake them at the top of La Liga.
Napoli are 10 points behind Serie A leaders Juventus but had a morale boosting 2-1 win over 2nd place Roma at the weekend.
Real are unbeaten in their last 11 Champions League matches heading into tonight's tie.