Cristiano Ronaldo and Paul Pogba face their former clubs when Manchester United take on Juventus in the Champions League on a matchday where Real Madrid coach Julen Lopetegui is condemned to win against Viktoria Plzen.

Ronaldo's return to Old Trafford has electrified fans ever since the group draw, having won the first of his five titles in the elite event with United in 2008, the year before he moved on to Real.

Tuesday is Ronaldo's second trip back to United, the first being with Real in 2012-13, and Juve goalkeeper Wojciech Szczesny knows it will be another special occasion for the Portugal star.

"We all know how important things he has done there, but he is now a Juventus player and we are also really appreciating what he is doing here," Szczesny said.

"It will be a great Champions League night, United are strong, and like us they will also try to win."

Juve hope finally to lift the trophy again after losing finals in 2015 and 2017, and Ronaldo's arrival from Real is a clear signal of intent.

The Italians top group H with a maximum six points from United who have four. Both sides played to draws on the weekend, with Juve surprisingly held 1-1 by Genoa and United conceding a stoppage-time equalizer at Chelsea.

"We need to focus on and we need to win because it is important to win our home games in the Champions League," United's Luke Shaw told club TV.

The two sides have not met since 2003, with United winning the last three of their 12 games overall.

The Chelsea draw further eased the pressure on coach Jose Mourinho, and the French world champion Pogba will want to show his class against the side he played for between 2012 and 2016 before returning to Old Trafford.

Former Spain coach Lopetegui is far worse off than Mourinho as anything but a victory against the Czech minnows Plzen would very likely spell the end of his term at Real who have been struggling since Ronaldo's summer departure.

The three-time reigning champions are winless in five games overall and have lost the last three, including their last Group G outing, 1-0 at CSKA Mowcow.

But Lopetegui insisted after Saturday's 2-1 league home loss against Levante: “I have more desire than ever to continue because the team gave everything.”

Real's next league match is a visit to Barcelona Sunday for the season's first Clasico which like Barca's Group B topper Wednesday against Inter Milan will take place without Lionel Messi who broke his arm in Saturday's 4-2 league win against Sevilla.

But coach Ernesto Valverde is not concerned, saying: “There are games when he has not played from the start and we have played with the same idea.

Valverde will continue with Gerard Pique and Clement Lenglet in centre defence with Thomas Vermaelen and Samuel Umtiti still out.

Inter could miss key midfielder Radja Nainggolan, who was substituted in Sunday's Milan derby Inter won in stoppage time from captain Mauro Icardi.

“Our head is already focused on Barca,” Icardi said shortly afterwards.

Also tied on a maximum six points are high-flying unbeaten Bundesliga leaders Borussia Dortmund and 2014 and 2016 runners-up Atletico Madrid going into their clash in Germany.

"We are ready for Atletico Madrid," vowed Dortmund's Germany forward Marco Reus, and their England teenage sensation Jadon Sancho insisted that "we have big ambitions.

At the other end of the spectrum Tottenham must finally deliver when they visit PSV Eindhoven for a duel of zero-points teams in the Barcelona group.

"If we are not capable of winning this type of game we cannot win the title," manager Mauricio Pochettino said.

And in Group C three-time Champions League winning coach Carlo Ancelotti is at his former side Paris Saint-Germain with leaders Napoli.