Wednesday 28 September 2016 06:44, UK
It was a good night for English clubs as Leicester and Tottenham earned 1-0 victories in the Champions League.
Here we pick out five things that we learned from Tuesday's European action...
The Foxes might have suffered as many Premier League defeats already this season as during the entirety of their title-winning campaign, but they made it back-to-back wins in the Champions League with a 1-0 win at home to Porto.
This was classic Leicester, getting their goal and then riding the subsequent storm while playing on the counter-attack. Their seventh 1-0 win of 2016 showed that Claudio Ranieri's men can still do the business when they are fully focused on the task in hand.
Perhaps that's how it will be for them this season. A repeat of their Premier League success might be too much to ask but the challenge of Europe is a new one for these players. It's one they appear to be ready to embrace.
The arrival of Islam Slimani certainly gives Leicester something they didn't have last season. He had marked his Premier League home debut with two goals and followed it up with the winner on his first Champions League appearance for the club.
Porto already know all about the Algerian - this was his sixth goal in four games against them in 2016 alone having haunted them with Sporting prior to his arrival in England - but stopping him is clearly another matter.
Ranieri had previously been forced to choose between the aerial presence of Leonardo Ulloa and the mobility of Shinji Okazaki. In Slimani, he has both of those key qualities rolled into one package. It's makes for a formidable foil for Jamie Vardy.
Heung-Min Son has timed his purple patch well.
The South Korea international netted his fifth goal in as many games on Tuesday, setting Spurs on their way to a crucial Champions League away win over CSKA Moscow.
The injury to Harry Kane was viewed as the ideal opportunity for summer signing Vincent Janssen to step up to the plate, but the Dutchman's struggles stand in stark contrast to Son's fine form.
He latched on to Erik Lamela's pass and squeezed a low shot past Igor Akinfeev on 71 minutes, securing a much-needed victory for Tottenham after their disappointing defeat to Monaco.
"I think it is key," Pochettino said of Son's recent success. "It is very important that not only Harry, who was good before his injury and scored, that now another player has scored and that is very important for the team.
"I feel very pleased for Sonny. He is on fire and to keep this form is very important for us."
Meanwhile, Janssen will perhaps allow himself a rueful smile. He toiled for more than an hour before being replaced by Georges-Kevin N'Koudou and just four minutes later, Tottenham were ahead. When your lucks out, it's out.
Cristiano Ronaldo moved a step closer to becoming the first player to score a century of European goals in Real Madrid's Champions League draw with Borussia Dortmund on Tuesday night.
The Portugal international gave the visitors the lead after 17 minutes with a neat close-range finish for what was his 95th goal in Europe's premier club competition.
That strike was also the forward's 98th in total in European football, and he may even have brought up his century but for a little more luck at the Westfalenstadion.
Ronaldo saw a header correctly ruled out for offside in first-half injury time, before twice going close in the second period, although it surely will not be too long before he reaches the landmark.
While Real Madrid may feel aggrieved not to have recorded their first-ever win at the Westfalenstadion on Tuesday evening, they were in many ways fortunate to escape with a 2-2 draw against Borussia Dortmund.
Their increasingly busy goalkeeper Keylor Navas - back after a four-month injury layoff - forced into making eight saves against the Bundesliga side, more than he has made in any other competitive game for the La Liga club.
The holders also faced 20 shots against Dortmund, the most in any competitive match since Zinedine Zidane took charge of Los Blancos in January, as Real were held for a third encounter in a row.