The draw for the semi-finals of the Champions League takes place this Friday at 11am in Nyon, Switzerland.
Here we look at the four teams vying to make it to the final in Lisbon on May 24 (a match you can watch live on ITV and on this website).
Team: ATLETICO MADRID
Best: Runners-up (1974)
Star man: Diego Costa
Overview: This year's surprise package. Pulled off the shock of the tournament when they dumped four-time winners Barcelona out in the quarter-finals. Have looked irresistible at times this year thanks to the invention of Koke and Diego Costa's eye for goal. The Primera Division leaders also beat AC Milan 5-1 on aggregate in the last 16.
Team: BAYERN MUNICH
Best: Winners (1974, 1975, 1976, 2001, 2013)
Star man: Arjen Robben
Overview: Pep Guardiola is hoping to join an exclusive club of coaches who have won the Champions League with two different clubs. Bayern won the Bundesliga with a record seven games to spare this year, but they had to work hard to see off Manchester United and make their third successive Champions League semi.
Best: Winners (2012)
Star man: Eden Hazard
Overview: No-one fancied Chelsea to win the competition in 2012 and that was the case earlier this year. But many are starting to believe it could happen all over again after Demba Ba's last-gasp winner against Paris Saint-Germain's. If Chelsea lift the trophy, Mourinho will become the first manager to have won the Champions League with three different clubs. Now that is special.
Team: REAL MADRID
Best: Winners (1956, 1957, 1958, 1959, 1960, 1966, 1998, 2000, 2002)
Star man: Cristiano Ronaldo
Overview: After a 12-year wait, this could finally be the season when Real Madrid finally achieve la decima (the 10th European Cup). Without the injured Cristiano Ronaldo, Madrid lost 2-0 in their second leg against Borussia Dortmund but thankfully for the Spaniards, they had already done enough damage the previous week at the Bernabeu.
Watch Demba Ba put Chelsea through with a late goal against PSG: