The Champions League and Europa League quarter-final draws begin at 1100 GMT on Friday, with the eight teams left in each competition set to discover who stands between them and a place in the final.
The draw for the last eight of the two tournaments will be followed by the draw for the semi-finals, meaning that the clubs involved will have their routes to Wembley and Dublin mapped out at UEFA headquarters in Nyon.
Barcelona are the overwhelming favourites to lift what would be a fourth European Cup, while domestic rivals and nine-time winners Real Madrid find themselves in the draw for the first time in seven years.
Without country protection the Spanish giants could face each other, as could any two of the three English teams in the competition - Manchester United, Tottenham and Chelsea.
Schalke are Germany's sole remaining representatives, while reigning champions Inter Milan are the only Italian club left in Europe. The eighth quarter-finalists are Shakhtar Donetsk, making their debut at this stage in the competition and hoping to emulate the achievement of fellow Ukrainian side Dynamo Kiev, who reached the Champions League semi-finals in 1999.
Questions of who could play who have been going on since Shakhtar and Barcelona qualified last Tuesday, with the Catalans the team that most will want to avoid - described by Chelsea boss Carlo Ancelotti as "the most dangerous" side left in the competition.
Spurs manager Harry Redknapp has also admitted he would prefer not to draw Barca, but Manchester United supremo Sir Alex Ferguson insists he has no such fear should his side face a rematch against the Spanish giants, who defeated them in the 2009 final in Rome.
"It is not good tactics to go into how good Barcelona are and show a trepidation or apprehension about it," Ferguson said. "I don't think that is our way. You have to face every hurdle as it comes along.
"We have the experience of playing Barcelona recently. We knocked them out in the semi-final and then lost the final to them in Rome the following year.
"There is no point trying to pick what you think would be the best one for you," said Ferguson. You can underestimate some of them that way. Anyone who has got themselves into this position must have qualities; either certain players, or a good home record.
"Shakhtar Donetsk look as if they are pretty useful and Schalke knocked out Valencia and we know how difficult it was for us against them. As soon as the draw is made you are into your file on them to build up your knowledge. Everyone will get the same attention from me."
In the Europa League, Portuguese sides dominate the quarter-final line-up with runaway league leaders Porto, who are still on course to achieve a Treble, joining Benfica and Braga in the last eight.
Dutch champions FC Twente, Spartak Moscow, Villarreal, PSV and Dynamo Kiev make up the remaining contenders.
Champions League quarter-finalists: Barcelona (Spain), Shakhtar Donetsk (Ukraine), Tottenham Hotspur (England), Schalke 04 (Germany), Manchester United (England), Inter Milan (Italy), Chelsea (England), Real Madrid (Spain)
Europa League quarter-finalists: Braga (Portugal), Dynamo Kiev (Ukraine), PSV Eindhoven (Netherlands), Villarreal (Spain), FC Porto (Portugal), Spartak Moscow (Russia), FC Twente (Netherlands), Benfica (Portugal)