Uefa Champions League group stage guide: VAR, kick-off times and everything you need to know

The Champions League returns on Tuesday as Liverpool aim to go one better and win their first trophy under Jurgen Klopp.

They are joined in Europe's leading club competition by domestic rivals Manchester United, Manchester City and Tottenham and face a tough examination against Thomas Tuchel's Paris Saint Germain in their group stage opener.

The Reds welcome PSG following Saturday's 2-1 victory over Spurs, while Mauricio Pochettino's men must pick themselves up for a trip to Inter Milan. Hugo Lloris and Dele Alli remain sidelined for the trip to the San Siro, with Kieran Trippier and Toby Alderweireld left back in London for what Mauricio Pochettino called "technical reasons".

On Wednesday, Manchester United visit Young Boys with City welcoming Lyon as Pep Guardiola attempts to win the trophy which would confirm his current side as one of the Premier League era's best.

Below, we examine what to look out for in the 2018-19 competition.

What are the highlights of the group stages?

The competition has the potential to get off to a flying start this season with some interesting match-ups in the group stages. Indeed, some even take place this week. Liverpool's opener against PSG is certainly eye-catching, as is Roma's trip to Real Madrid and Valencia versus Juventus. Tottenham's clash with Inter Milan is another to make the mouth water, coming as a reminder of some memorable encounters in 2010. Further ahead, Barcelona lie in wait for both those teams while Liverpool, last season's runners-up, will also face Napoli. Paul Pogba's return to Juventus with Manchester United will also attract plenty of attention when that takes place in November.

Will there be a different winner?

It is always difficult to look beyond Real Madrid and the Spanish giants - who have won four of the past five titles and 13 European crowns overall - will again be among the leading contenders. But this is a new era at the Bernabeu with Zinedine Zidane, the man at the helm for the successes of the past three years, and star player Cristiano Ronaldo having left. Manchester City, Barcelona, PSG, Juventus - with Ronaldo now in their ranks - and Bayern Munich are rated as the sides most likely to relieve them of their crown.

Are the likes of Manchester City and PSG ready to come of age?

Some of Europe's established elite have been looking over their shoulders at the rise of the so-called 'new-money' clubs for a number of years now. Both City and PSG looked formidable as they excelled in the group stages last season but they were unable to progress much further, falling to Liverpool and Real Madrid respectively. They are not going away, however. Their ambitions are clear and they will certainly be aiming to make serious challenges.

Have there been any changes to the format

he qualifying process may have changed - with 26 teams now gaining direct entry - but the format of the group stages remains largely untouched. The only noticeable difference concerns kick-off times. The previous uniform 7.45pm starts have been scrapped and replaced by a staggered system to suit broadcasters. On each group stage evening, two games will kick-off at 5.55pm with the remaining six at 8pm.

Will VAR be used?

The video assistant referee is coming to the Champions League - but not just yet. Following the success of the system at the World Cup, it is inevitable it will be brought into UEFA's elite competition but Europe's governing body appear to be thinking in terms of next season. This is certainly not because of any lack of confidence in the decisions being made, but more over concerns about technical logistics and the training of officials. It has been suggested it could be brought in for this season's final, or even from the quarter-final stage but no firm decisions have been taken.

When and where is the final?

The showpiece fixture will take place at Atletico Madrid's Estadio Metropolitano on Saturday, June 1.