Holders Manchester United will face familiar foes Celtic in this season's Champions League group stage.
United, who beat Chelsea on penalties to lift the European Cup for the third time last May, were also drawn on Thursday with Villarreal of Spain and Champions League debutants AaB Aalborg of Denmark in their opening matches in Group E.
Chelsea will face AS Roma of Italy, Girondins Bordeaux of France and Romanian debutants CFR Cluj in their opening games in Group A.
European giants Real Madrid and Juventus were drawn together in Group H along with UEFA Cup holders Zenit St Petersburg and BATE Borisov of Belarus, who are both playing in the competition for the first time.
Liverpool, five time European champions, who survived a scare before beating Standard Liege of Belgium 1-0 in extra time on Wednesday to qualify for the group stage, will face PSV Eindhoven, Atletico Madrid and Olympique Marseille.
The competition proper starts on Sept 16-17 with the final in Rome on May 27 next year.
John Reid, the chairman of Celtic said he was "absolutely delighted" to be drawn against United with the first game scheduled for Old Trafford on October 21 and the return at Celtic on November 5.
"The clubs go back a long way and many Celtic fans have a soft spot for United, but of course they won't when we play them," he said.
"We had two fantastic games with them two seasons ago, losing 3-2 at Old Trafford and beating them 1-0 in Glasgow to qualify for the last 16 and Alex Ferguson won't want a repeat of that defeat."
HUGE GAMES
United's chief executive David Gill said: "The games against Celtic will be huge. I am sure the players and the fans are all looking forward to that one fixture in the calendar."
United open the defence of their title with a home match against Villarreal on September 17.
There is also a fascinating series of games in Group B with Inter Milan, looking to become European champions for the first time since 1965 under new coach Jose Mourinho, facing Werder Bremen, Panathinaikos of Greece and debutants Anorthosis Famagusta of Cyprus.
Mourinho, who won the competition with Porto in 2004, told his club's website (www.inter.it): "Even after seeing the teams we have to face, you never know if it will be an easy first phase or a difficult one.
"Our first aim is to get through the group, our second is to try to finish first in Group B. Certainly we are very motivated and confident, we want to start playing in the Champions League as quickly as possible."
There could hardly be a greater contrast between two clubs than nine-time European champions Real Madrid and BATE Borisov of Belarus who will be competing in the Champions League for the first time. They meet in the opening match at the Bernabeu on September17.
"BATE Borisov are a modest side who you have to show respect towards because every team can spring a surprise, and if you lose points at the start they can be difficult to make up later on," Real sports director Predrag Mijatovic told club website www.realmadrid.com.
There will be a memorable homecoming for Fernando Torres, who left Atletico Madrid a hero for Liverpool last year and has since become a hero at Anfield after scoring 32 goals in his debut season for the club.
Liverpool travel to Madrid on October 22 but Atletico's Argentina forward Sergio Aguero played down talk of a showdown with his former strike-partner Torres.
"It isn't a clash between Torres and Aguero. It is 11 against 11, Atletico against Liverpool. Torres is a great player but they have lots of other ones as well," he said.
(additional reporting by Mark Meadows, Felix Tabitabe and Mark Elkington)
(Editing by Justin Palmer)
