Ronaldo and Mbappé in Champions League Opta numbers

There is still lots to play for on matchday six as the Champions League group stage draws to its conclusion.

Barcelona and Juventus are already through but Tuesday should see Lionel Messi and Cristiano Ronaldo face off once again, the latter looking to end a dry spell in front of goal against the Catalans.

Kylian Mbappé is another star enduring a comparatively rotten run when it comes to goalscoring, but Istanbul Basaksehir could represent ideal opponents for the Paris Saint-Germain forward.

Elsewhere in a finely poised Group H, RB Leipzig host Manchester United in a critical game for both – and one where Marcus Rashford could earn a slice of history.

Barcelona v Juventus: Can Ronaldo end barren run?

This match will be the sixth time Messi and Ronaldo have met in the Champions League and the first since May 2011, the former leading 3-0 in terms of goals scored in those contests.

Indeed, while he has hit 15 goals in his past 20 appearances against Barca in all competitions, Ronaldo has played more Champions League matches (five) against the Catalans without scoring than he has against any other opponent.

Barca, who need only avoid defeat to make sure they win the group, are unbeaten in four Champions League meetings with Juve and have not lost at home to the Bianconeri since April 2003.

In fact, Juve have gone four games without scoring against Ronald Koeman's side. Since Giorgio Chiellini's goal in a 3-0 victory back in April 2017, they have gone 395 minutes without finding the net against Barca.

Chelsea v Krasnodar: Why Lampard's side are hard to beat

With first place in Group E already secure, Frank Lampard will have the luxury of rotating his line-up for the visit of Krasnodar to Stamford Bridge.

Chelsea have won all five previous games against Russian teams in the Champions League by an aggregate score of 13-1, and if they can continue that 100 per cent record, they will record their highest points tally (16) for a single group stage.

The Blues have proven seriously tricky opponents to breach this term. They are the only side yet to face an Opta-defined 'Direct Attack' in the 2020-21 Champions League – a sequence that starts in a team's own half and finishes with either a shot or a touch inside the box, with at least 50 per cent of the movement going towards the opposition goal. They also boast a goalkeeper in Edouard Mendy who has the best save percentage (93.8) of any keeper to play in at least three games in this season's competition.

Having scored four goals against Sevilla last time out, Olivier Giroud could well be given another chance to impress. The striker has five goals from six shots on target this term and has scored at least 10 more goals than any team-mate since the start of 2018-19 (16 goals in total). Only Didier Drogba (36) and Frank Lampard (25) have got more for the club in European competition outside of qualifying rounds.

Paris Saint-Germain v Istanbul Basaksehir: Mbappé desperate to end goal drought

Their 3-1 win at Manchester United last time out means Paris Saint-Germain know a win over Istanbul Basaksehir will see them finish top of a seriously competitive Group H.

They have won five of their previous six home games in the competition and kept a clean sheet in all those victories, so Thomas Tuchel will surely fancy his side's chances, especially since Basaksehir could become just the ninth side in history to concede at least four goals in three games running.

Mbappé will certainly hope to be on the scoresheet. The striker, who reached 100 goals in all competitions for PSG at the weekend, has failed to score in his past nine Champions League games, attempting 27 shots in that run with an Expected Goals total of just 3.9.

PSG will need to be wary of Edin Visca, though. The winger has carried the ball 1,264 metres in the group stage, second only to Bayern Munich's David Alaba (1,465).

RB Leipzig v Manchester United: Rashford could unlock pressing machine

Manchester United thrashed RB Leipzig 5-0 at Old Trafford but they have lost their previous two Champions League away games against German sides, going down 3-1 to Bayern Munich in April 2014 and 3-2 to Wolfsburg five years ago.

With Leipzig having won three home games in a row in Europe with just one goal conceded, they will feel confident of avenging that previous loss and inflicting upon Ole Gunnar Solskjaer a sixth defeat in 11 Champions League games, which would represent the worst return for a manager of an English club.

Leipzig's pressing intensity is renowned: they have allowed opponents an average of 8.4 passes before a defensive intervention, the lowest number of any team in 2020-21.

Still, they must beware the United counter-attack and, in particular, Marcus Rashford. The England star has scored three goals following a ball carry this season, the most of any player, and is attempting to become the first Englishman to hit six goals in a single Champions League group stage.

Other fixtures:

Lazio v Club Brugge

1  – If Lazio avoid defeat, they will remain unbeaten in a Champions League group stage for the first time since 1999-00, while this will also be the first time they have reached the knockout stages of the competition since that campaign.

3  – Club Brugge are looking to win consecutive Champions League games for the first time since November 2005. However, they have never won three games in a single Champions League group stage before.

Dynamo Kyiv v Ferencvaros

16  – Dynamo Kiev (13) and Ferencvaros (12.4) have the largest Expected Goals Against figures amongst the sides in the Champions League this season, with Ferencvaros conceding more goals than any other team (16).

13.9  –  Ferencvaros' opponents have kept the ball for 13.9 seconds per sequence on average in the Champions League this season, the longest of any side's opponents this season.

Rennes v Sevilla

0  – Sevilla have never lost their final Champions League group-stage game (W3 D2). In the history of the competition, they have played more matchday-six group-stage games without defeat than any other side (including the second group phase).

90  –  Only Barcelona (92) have had more shots than Sevilla in the Champions League this season (90), though Sevilla have converted just 6.7 per cent of their shots in the competition this term (six goals).

Zenit v Borussia Dortmund

10  – No side has had fewer shots on target in the Champions League this season than Zenit (10), with the Russian side failing to register a single effort on target in two of their five games this season (including the reverse fixture versus Borussia Dortmund).

0 – Dortmund are seeking consecutive away wins for the first time since October 2016. They have won their previous two games on matchday six of the group stage and could make it three such victories in a row for the first time.