Champions League holders Real Madrid will face former European champions Liverpool, FC Basel and debutants Ludogorets of Bulgaria following the group stage draw on Thursday.
The eagerly-awaited event, held at the Grimaldi Forum in Monte Carlo, had a distinct air of deja vu about it.
Bayern Munich and Manchester City were drawn in the same group for the second successive season, as were Chelsea and Schalke 04, and Arsenal and Borussia Dortmund.
Barcelona and Paris St Germain, both clubs with strong links to Qatar, will also face each other in a mouth-watering clash.
Real won the title for a record-extending 10th time when they beat Atletico Madrid 4-1 after extra time in Lisbon in May and have the chance to avenge a 5-0 aggregate defeat by five-time champions Liverpool in the last 16 in 2009 when they lost 1-0 at the Santiago Bernabeu and 4-0 at Anfield.
Further back in time Liverpool beat Real 1-0 in the 1981 European Cup final in Paris.
Real will open the defence of their crown when they host Basel in a Group B match on September 16 and will visit the minnows of Ludogorets on October 1. They face Liverpool at Anfield on Oct. 22 with the return leg in Madrid on Nov.4.
As well as facing Liverpool, back in the Champions League for the first time since 2010, and Basel, Real will also play Ludogorets who were described as "the fairytale club" by UEFA general secretary Gianni Infantino during the draw.
Ludogorets qualified for the group stage for the first time with a 6-5 penalty shootout win over former champions Steaua Bucharest in an amazing finale to their match on Wednesday.
Ludogorets defender Cosmin Moti went in goal after keeper Vladislav Stoyanov was sent off in the last minute of extra time.
He then scored the first penalty in the shootout before saving two other spot kicks as Ludogorets went through.
"I'm happy with the draw," Ludogorets coach Georgi Dermendzhiev told local bTV channel.
"Real Madrid will light up Bulgaria.
"Liverpool are a very strong team too and we know Basel because we met them last year in the Europa League. I can assure you that you'll see a stronger Ludogorets from now on."
"We know it's going to be very tough," said Cristiano Ronaldo of the Liverpool tie.
"In general the group is nice, it's good for Real Madrid.
"We are going to try and do the same again this season. We're going to try to win the Champions League. It will be difficult but Real Madrid are always thinking big, thinking huge."
Real Madrid, who waited 12 years to secure their 10th title, are bidding to become the first club in the Champions League era to win the trophy in successive seasons, a feat achieved fairly regularly under the old European Cup format.
The last team to win the title in successive seasons were AC Milan in 1989 and 1990, but Cristiano Ronaldo, who scored 17 goals in the competition for Real last season, sees no reason why they cannot retain their crown.
Speaking at the draw ceremony after picking up an award as the best player in the competition last season, the Portugal winger was asked by compere and former Manchester United goalkeeper Peter Schmeichel, if Real could win it again.
"Why not? Everything is possible. I've won it with Manchester United and now with Madrid, so we're looking forward to another one."
Many teams were drawn together again, including Bayern and Manchester City who meet for the third time in four seasons.
Bayern and Manchester City were joined by CSKA Moscow for the second straight season too with AS Roma completing the quartet in Group E.
Txiki Begiristain, City's director of football told reporters: "Last season Bayern were first, we were second and we also played CSKA, and the fourth team now is very tough, a very strong team in AS Roma.
"All the clubs try to play good football, so it will be an amazing group."
Last season City midfielder Yaya Toure was racially abused at CSKA leading European football's governing body UEFA to order a partial closure of their stadium.
Last term Bayern won 3-1 in Manchester before City won the return 3-2 in Munich as both teams qualified from the group.
Bayern chairman Karl Hopfner told reporters: "We know the teams well after facing Man City and CSKA last year and Roma will not be easy either. I think it is the toughest group by far."
Last season's runners-up Atletico were grouped with former champions Juventus, Olympiakos Piraeus and Malmo of Sweden in Group A.
Barca and PSG will also face former European champions Ajax Amsterdam and APOEL Nicosia in Group F.
Another intriguing draw pitted Barca with PSG, Ajax and APOEL. Barcelona and the Paris club have strong links with Qatar - PSG are now owned by the Qatari Investment Authority and Barca are heavily backed by the Qatar Foundation.
PSG's Sweden striker Zlatan Ibrahimovic also has close links with both teams, having also played for Barca, and will no doubt relish the matches against his former team mates.
The competition gets underway on September 16 with this season's final at the Olympic Stadium in Berlin on June 6.
