Chelsea travel to Spain to face Real Madrid in the first leg of their Champions League semi-final tie on Tuesday night.
Thomas Tuchel's side progressed into the last four after a 2-1 aggregate win over FC Porto. While Real saw off Liverpool in a 3-1 win.
Here are the all-important statistics ahead of the huge Champions League knockout clash:
• The teams have met in only three previous fixtures – in two UEFA finals which were both won by Chelsea, who are therefore unbeaten against Madrid.
• This is their first meeting since the 1998 UEFA Super Cup in Monaco, when a Gustavo Poyet goal seven minutes from time at the Stade Louis II gave UEFA Cup Winners' Cup holders Chelsea victory against Madrid, who had qualified by winning the UEFA Champions League.
• Madrid have won their last three semi-final ties, having lost five of the previous six.
• This is Madrid's 14th appearance in the UEFA Champions League semi-finals, a competition record, two more than Barcelona and Bayern.
• Madrid have won six of their last eight UEFA Champions League matches (D1 L1) having managed one victory in their previous six (D2 L3). They have lost seven of their last 21 games in the competition (W10 D4).
• Despite this season's victories against Inter, Mönchengladbach, Atalanta and Liverpool, Madrid have won only five of their last 11 home European games (D2 L4).
• Madrid's record in two-legged knockout ties against English clubs is W9 L5; they have won four of the last five, the exception last season's defeat by Manchester City.
• The first-leg loss to City last season was only Madrid's third at home to English clubs; their record otherwise is W9 D6. They were without a win in two games against English visitors in Madrid before beating Liverpool this season.
• This is Chelsea's 14th UEFA competition semi-final; their record is W6 L7.
• Chelsea's record in Spain following their quarter-final tie against Porto is now W6 D8 L7; the second-leg defeat was only their second loss in their last 15 matches in the country (W5 D8).
• This season's seven victories have made it ten wins in Chelsea's last 17 UEFA Champions League matches (D4 L3).
• Last season's home loss to Valencia was one of only four defeats in the Blues' last 28 matches against Spanish opponents overall (W10 D14). Before Matchday 5 this season, the Blues had won only one of their previous 11 fixtures against Liga clubs, home and away (D6 L4); they have now been victorious in their last three and have not conceded in the last four.
• The win at Sevilla in this season's group stage made it one defeat in their last 13 matches against Liga clubs in Spain (W4 D8).
• Chelsea have played 12 two-legged knockout ties against Spanish clubs (W5 L7), the last before beating Atlético this season in the 2017/18 UEFA Champions League round of 16 when they lost 3-0 at Barcelona in the second leg to go down 4-1 overall.
• The London club have won only three of their 12 away knockout games against Spanish teams in UEFA competition (D4 L5).
• Tuchel is unbeaten as a head coach against Spanish clubs (W3 D3).