The players are out - it's snowing in Munich - as the Champions League anthem blares out in two empty stadia.

Former Porto striker Benni McCarthy has been chatting to BBC Radio 5 Live.

The South African, who lifted the Champions League with Porto under Jose Mourinho in 2004, says the club could potentially do well tonight.

"They have really set the Champions League alight and going past Juventus with quality players like Ronaldo, it was amazing," he said.

"Chelsea is a completely different challenge. It's going to be extremely difficult for Porto but they do have strong beliefs and are not scared of anyone. They can cause lots of upset.

"[Porto manager] Sergio Conceicao has lots of passion and he is a born winner - he has craziness to him! It rubs off really well onto the players because you see them giving their all for the manager.

"Porto will fancy themselves, even though Chelsea are a big side."

Porto have won only one of their past 13 European knockout phase games against English opposition (D4 L8).

Chelsea have won nine of their last 10 games against Portuguese opposition (L1).

BBC Radio 5 Live

You can listen to live radio commentary of this game on BBC Radio 5 Live on this page.

This is Chelsea's first Champions League quarter-final in seven years.

In 2013-14 they beat PSG at this stage and lost to Atletico Madrid in the last four.

GosBoss: Need Mbappe and Haaland in the same league so we may get another Ronaldo and Messi rivalry.

Thomas Tuchel could become just the second Chelsea manager to win his first three games in the knockout stages of the Champions League. The previous manager to do this was Roberto di Matteo in 2011-12, the only time Chelsea won the competition.

Image source, Getty Images

Jared Maobe: Jorginho????? Like really????

More from Porto boss Sergio Conceicao: "Obviously we look at Chelsea and see that these weekly tests are much more competitive than ours.

"You can see that Chelsea's games are all extremely difficult, and that's an advantage for them.

"Anyway, when you enter the field, you don't think that we spent 25m euros and Chelsea 250m.

"We will not think that Evanilson was the most expensive player, at 8m, and the most expensive player in Chelsea was (Kai) Havertz, at 80.

"On the field it's 11 against 11, with a strategy defined according to each team's idea of play.

"There may be one or another variant of the game to face this opponent specifically, but from there on there is nothing impossible. Everything is possible."

Porto coach Sergio Conceicao says he wishes Chelsea had won at the weekend.

The Blues come into the game on the back of a 5-2 thrashing by West Brom.

"I wished they had won the last game rather than lost," said Conceicao.

"A defeat like that serves as a warning, it sets the alarm bells off and makes everyone more alert to danger. Chelsea had been very strong until this game, they have the second-best defence in the Champions League and are a strong side.

"Their last game barely formed part of our analysis of them, I'm more focused on what they did against Atletico Madrid in the Champions League, for example.

"Chelsea have several strengths that will be a real challenge for us to overcome."

Italian Serie A

A couple of big games in Italy have just finished.

Inter Milan are 11 points clear at the top after a 2-1 win over Sassuolo. Nine games to go.

Juventus, who lost to Porto in the last 16, are up to third after beating Napoli 2-1.

Image source, Getty Images

Of course, Paris St-Germain produced a headline-grabbing result in the previous round as they thrashed Barcelona 4-1 on their way to a 5-2 aggregate win.

Kylian Mbappe overshadowed Lionel Messi in that first-leg win, scoring a hat-trick as PSG reached the last eight for just the second time in the last five seasons.

"For me, the Champions League holds a very important place," Mbappe told Uefa.com.

"We've lost at different stages, we've suffered. I think that if I win it, there'll be a lot of emotion. The Champions League is, as the song says, for 'les meilleures équipes' (the best teams). Bayern are a great team. Now, it's just about being calm and confident in preparation for the first leg in Munich."

Image source, Getty Images

Bayern Munich's ex-PSG forward Eric Maxim Choupo-Moting knows all about tonight's opponents, and has warned his team-mates that they cannot put all their focus on stopping just Kylian Mbappe and Neymar.

"You have to be more than just aware of the pair of them; but not just those two," he said.

"There are so many top players in the team we have to keep an eye on. The important thing is that we play as a team and that's the strength of Bayern."

Image source, Getty Images

Paris St-Germain are pretty used to having it their own way in Ligue 1 but they are facing a real challenge from an unlikely source this season.

Lille are three points clear at the top of the table after beating PSG on Saturday, with Neymar marking his return from injury by getting sent off.

The Brazilian has picked up three red cards in his last 14 appearances for PSG and will be keen to avoid going in the referee's book tonight because if he is shown a yellow he will be suspended for the second leg.

Thumbs up if you believe Pepe is the sweetest person in the world. Thumbs down if you don't...

Image source, .

"Pepe is the sweetest person in the world, very affable, but when he goes on to the field, he has a very unique identity as a player, which sometimes doesn't reflect his personality, his nature, his feelings," said Nelo Vingada, the coach who brought him to Europe with Maritimo.

"I believe he has gained a reputation based on images from one or two Real Madrid games.

"As much as we like Pepe, it doesn't hurt to recognise that those were behaviours that didn't dignify him. That was not Pepe. The Pepe I know is the player from the other matches - sometimes aggressive, but always within the limits of football."

Read Marcus Alves' feature on Porto defender Pepe here.

Simon Gleave, head of sports analysis, Nielsen's Gracenote: "Chelsea are the outsiders of the three English clubs remaining in this season's Champions League but they received a favourable draw to reach the semi-finals.

"The Euro Club Index , externalgives Chelsea a 64% chance of reaching the last four by knocking out Porto.

"Chelsea's chance of winning the competition has risen to 8%, making the Blues fifth favourites of the eight teams remaining."

Image source, Gracenote

Chelsea manager Thomas Tuchel says "things got heated" in a "serious situation" between Kepa Arrizabalaga and Antonio Rudiger on Sunday.

Goalkeeper Kepa and defender Rudiger were involved in an incident in training the day after Chelsea's shock 5-2 defeat by West Brom.

"We needed to interfere in the situation, so that was serious," Tuchel said on Tuesday.

"They cleared the air immediately and there was nothing left the day after."

Tuchel said the argument stemmed from an incident in training and not the loss to West Brom.

"It got heated up between Toni and Kepa," the German said. "So we calmed the situation down immediately."

Tuchel said neither player would be punished after the players "immediately sorted it out" between themselves.