Arsenal face a seemingly impossible task in reaching the Champions League quarter-finals at the expense of Bayern Munich while holders Real Madrid head to Napoli in a strong position ahead of Tuesday's second legs.
Madrid came from behind at the Santiago Bernabeu to beat Maurizio Sarri's men 3-1, while Arsenal found themselves on the end of a 5-1 demolition job at the Allianz Arena.
Napoli's home record of one defeat in 13 matches across all competitions - although that loss came just nine days ago against Atalanta - at least gives them a fighting chance, but Arsene Wenger's side will have to score at least four past Bayern at the Emirates, a feat not managed by any team since Wolfsburg in January 2015.
We look at the most pertinent stats from the two fixtures, courtesy of Opta.
Arsenal v Bayern Munich
0 - No club has progressed in a Champions League knockout tie after losing the first leg by four or more goals. It has happened nine times previously before this year's competition.
10 - Since the beginning of the 2003-04 season, Arsenal have lost just 10 of their 62 home games in the Champions League. However, two of those defeats were in the last 16 at the hands of Bayern Munich in 2013 and 2014.
1 - The German side have won just one of their last six Champions League away games, having lost three times and drawing twice in that period.
3 - Thanks to his strike in the first leg, Arjen Robben has now scored in back-to-back Champions League appearances versus Arsenal. Only against CSKA Moscow has the Netherlands international scored in more consecutive games.
6 - Robert Lewandowski has been directly involved in six goals in seven Champions League games against Arsenal, scoring and assisting three goals when he has previously faced the Gunners.
Napoli v Real Madrid
11 - Real Madrid are unbeaten in their last 11 Champions League matches, having won six and drawn five. If they avoid defeat against Napoli, it would be their longest run without defeat in the Champions League or formerly known European Cup.
4 - Napoli have been eliminated on each of the previous four occasions where they have lost the first leg of a last-16 tie in European competition. Only four sides have previously progressed when trying to overturn a 3-1 deficit from the first leg.
523 - Cristiano Ronaldo has failed to score in his last five Champions League matches, which is a total of 523 minutes. Since scoring his first goal in 2007, only once has he gone more than five UCL games without a goal.
1 - Napoli have lost just one of their last 10 Champions League games, winning seven and drawing on two occasions. However, their one defeat came this season in a 3-2 loss to Besiktas.
6 - Six of Napoli's last nine Champions League goals have been scored (four) or assisted (two) by Dries Mertens.