Lionel Messi and Cristiano Ronaldo will meet in a mouthwatering clash in this season's Champions League after Barcelona and Juventus were placed in the same group in Thursday's draw.

Messi and Ronaldo will resume the rivalry they developed when the Portuguese superstar was at Real Madrid. Between them, they have won 11 of the last 12 Ballons d'Or.

The two heavyweights were drawn in Group G along with Dynamo Kiev of Ukraine and Ferencvaros, the Hungarian club returning to the group stage for the first time in quarter of a century.

Meanwhile, beaten 2020 finalists Paris Saint-Germain will have a chance for revenge against Manchester United, who ousted the French club in the last 16 two seasons ago.

PSG will also come up against RB Leipzig in Group H. The sides met in last season's semi-finals in Lisbon in August, with Paris winning 3-0 before losing to Bayern Munich in their first ever final appearance.

Completing the group is Istanbul Basaksehir, who are appearing in the tournament proper for the first time.

English Premier League champions Liverpool, who won the Champions League in 2019, will face Ajax as well as Atalanta and Midtjylland of Denmark in Group D.

Holders Bayern will take on Atletico Madrid and will also have a short trip across the border to Austria to take on Salzburg in Group A. Lokomotiv Moscow are other team in the section.

Other notable match-ups will see 13-time European champions Real Madrid meet Inter Milan in Group B and Chelsea come up against debutants Rennes as well as Europa League winners Sevilla  in Group E.

Chelsea signed goalkeeper Edouard Mendy from Rennes last week.

The group stage starts on October 20, and all six rounds of games will be crammed into eight weeks in a schedule that is even more packed than usual because of the coronavirus pandemic.

This season's final is scheduled to be staged in Istanbul, which was initially the host for last season's final before UEFA was forced into a change of plans because of the health crisis.

It remains to be seen whether spectators will be able to attend matches in the group stage.