An all-capital-city clash for a place in Lisbon commences tonight. Club historian Rick Glanvill and club statistician Paul Dutton are joined by former Chelsea player Scott Minto for their look at this semi-final…
After the breathtaking 2-0 comeback against Paris Saint-German in the previous round, Chelsea will be happy to be playing this away leg first, though any similar lapses to those in the Paris game may put the tie beyond salvation even at the Bridge.
Atletico Madrid are Primera leaders, the only unbeaten side left in the Champions League and have won all their games at home to date, including against Barcelona in the quarter-finals.
In many ways they epitomise the kind of side against whom the Blues sometimes struggle: well-organised, tough to break down and unsparing in front of goal. And Chelsea are still smarting from the home defeat by Sunderland.
Yet history shows that we are often at our best in the face of the biggest challenges and a third Champions League final is just two stellar performances away. Magic happens and reputations are moulded in this knockout phase.
Jose Mourinho, facing his eighth semi-final challenge, will be determined to take a third team into the last two of the world's elite club competition, and to win it for a third time.
With a Sunday showdown at Liverpool on the horizon, this could be a huge week against his former clubs for Fernando Torres, who has reserved some of his best moments for the Champions League.
A sensation at youth level, he broke into the Atletico first team aged 17 and was captain at 19. His goalscoring heirs have included Sergio Aguero, Radamel Falcao and current incumbent Diego Costa.
Out with a slight knee problem, though, is Samuel Eto'o, who has a fine record against Atletico from his days with Real Madrid, Mallorca and Barcelona, striking seven times in 12 appearances.
Petr Cech appears to have recovered from the illness that cost him a place in Saturday's line-up, though Branislav Ivanovic is absent as a result of receiving his third yellow of the campaign in the 2-0 success over Paris Saint-Germain. The coaching staff may ask Cesar Azpilicueta to swap flanks with Ashley Cole coming in at left-back.
A final concern is the availability of Eden Hazard. Shortlisted for the Professional Footballers' Association Footballer of the Year and Young Footballer of the Year awards, the Belgian game-changer has not played since coming off soon into the PSG victory a fortnight ago but travelled to Spain yesterday.
His speed and ingenuity have been missed in the Premier League, especially in the surprise defeat to Sunderland.
After that loss Chelsea's magnificent home record under Jose Mourinho has not 'gone', as some have said. The run has ended but the extraordinary 77 games unbeaten may well stand forever as a monument to a golden age for this club.
And in eight days' time, in the second leg at the Bridge against tonight's opponents, we embark again on the campaign to match it. The two managers know and respect each other. Rojiblancos coach Diego Simeone faced Jose Mourinho's Real Madrid side four times, suffering three straight Primera beatings before achieving a Copa del Rey final win.
The Argentinean will be relieved goalkeeper Thibaut Courtois looks in line to play against his parent club tonight. Unlike the Premier League, UEFA has no rules to prevent this happening. This season the Belgian has kept 26 clean sheets in 49 games in all competitions.
Star striker Diego Costa suffered a deep gash in his shin in a recent game and did not quite look himself against Elche at the weekend. He has missed four penalties this season and the man who took over spot-kick duty, David Villa, squandered one from 12 yards on Saturday. Their second penalty of the game was dispatched - by Costa.
Football snobs scoff at those who mistakenly call our opponents 'Athletico', but the Spanglish idiom has some foundation in the club's history.
Atletico were formed in the country's capital by Basque students playing as Athletic de Madrid, after the most famous club from their home region, Athletic Bilbao, whose name reflected their strong English influence.
However in May 1940 ruling nationalist dictator General Franco ordered that foreign words should be purged from the public gaze and the restyling of both clubs as the more Spanish Atletico followed. In the 1970s, after Franco's death and the restoration of democracy, Bilbao reverted to their original anglophile nomenclature, while the Madrid side saw no such need.
Both tonight's teams have four players one booking away from missing the second leg. Frank Lampard, David Luiz, John Mikel Obi and Willian and, for Atletico, captain Gabi, Emiliano Insua, Koke and Juanfran.
On Sunday, just three days before the second leg at the Bridge, we have the trip to Anfield; Atletico kick off two hours later at Valencia's Mestalla.
Both sides are challenging on two fronts. Chelsea are one step away from a fourth UEFA final in seven years and are still in the domestic title race.
The Rojiblancos are closing in on their first La Liga title for 18 years. Their only Champions League final (back when it was the European Cup) was in 1974. They did, though, lift the Europa League the same year Chelsea scooped the big one, 2012, and won the resulting Super Cup by a convincing 4-1 margin.
This week's semi-finals
Atletico Madrid v Chelsea
Real Madrid v Bayern Munich
The UEFA Champions League final will be played in Benfica's 65,000-capacity Stadium of Light in Lisbon on Saturday 24 May.
Champions League top scorers
Cristiano Ronaldo 14 goals 710 minutes played
Zlatan Ibrahimovic 10 goal 646 minutes played
Lionel Messi 8 goals 630 minutes played
Diego Costa 7 goals 405 minutes played
Click on tabs above for more briefing.
WE HAVE HISTORY
Our clubs have only met in one other tie in the Champions League. That was in the 2009/10 group stage and the game at Vicente Calderon was in early November 2009.
Didier Drogba had a huge impact on his return from a three-match ban for publicly criticising the performance of referee Tom Ovrebo.
The Ivorian was handed an early opportunity by a defensive error but dragged his shot wide, then hit the post early in the second half. Atletico also had chances in what was often a tepid opening hour. Then the hosts took the lead through substitute Sergio Aguero, the Argentinean volleying a deep, deflected cross past Petr Cech.
Gradually Chelsea began to dominate the Spaniards, though, and Drogba was at the heart of it. His equalising goal was a shrewd header from a Florent Malouda ball (pictured below) and, six minutes later, an Ashley Cole pass sent him clear. His first shot was blocked by the goalkeeper but a follow-up found the target.
Aguero shocked the Blues with a brilliant injury time free kick to level the scores at 2-2.
The Colchoneros came third and transferred to the Europa League, which they eventually won beating Fulham 2-1 after extra-time in the final in Hamburg.
Our teams last met in the 2012 UEFA Super Cup in Monaco. Atletico, helped by an opportunistic first-half hat-trick by Falcao, won the showpiece 4-1. Gary Cahill scored with 15 minutes to go after Miranda had made it 4-0 on the hour.
Our previous meetings in the Champions League
21 October 2009, group stage
Chelsea…..……..…..4 Atletico Madrid………..……0
Kalou 40, 52
Perea og 90
3 November 2009, group stage
Atletico Madrid.…..2 Chelsea………..……2
Aguero 66, 90+1 Drogba 82,88
Chelsea's biggest away win in the Champions League
20/10/1999 - Galatasaray 0-5 Chelsea - First group stage
Atletico's biggest home win in the Champions League
11/09/1996 - Atletico 4-0 Steaua Bucharest - group stage
06/11/2013 - Atletico 4-0 Austria Vienna - group stage
Chelsea lost to a Spanish team in the Champions League: 2,981
Atletico lost at home: 70
Arsenal won a trophy: 3,258
Liverpool won the league: 8,753