OVERVIEW: IT is strange indeed not to find the side from Portugal’s second city not inhabiting the Champions League group stages. But after eight years making the group stages and frequently better, that is Sergio Conceicao’s side’s fate, having came a cropper in the qualifying rounds to Krasnodar of Russia. Incidentally, the last time they failed to reach the Champions League group stage, back in 2011, they went on to win this competition outright. Celtic fans will remember their victory in this competition’s forerunner in Seville in 2003, a year before Jose Mourinho marched his team all the way to become continental champions outright in Gelsenkirchen.

DEFENCE: With veteran goalkeeper Iker Casillas still not fit to play after a heart problem, the headline name in this list is Pepe, who is back at the club after a stellar career for both Real Madrid and Portugal. He played in the famous 1-1 Champions League group stage draw between these two sides back in 2005 when Ross McCormack scored a priceless equaliser for Alex McLeish’s under pressure side.

For all his undoubted class, Pepe is equally famed for his habit of involving himself unnecessarily in the unseemly side of the game. Likely to be paired alongside 32-year-old Spanish defender Ivan Marcano, Porto hold an extremely high back line and push their full backs forward. Consequently, there is encouragement for Steven Gerrard here that their offside line could be breached with a well-timed run from deep from the likes of Alfredo Morelos or perhaps Ryan Kent.

Goalkeeper Agustin Marchesin has international caps for Argentina on his resume but he only moved to the club this summer and didn’t look particularly clever in the recent defeat at Feyenoord. He likes to parry the ball out and can be theatrical at times.

Full backs Wilson Manafa on the right and Alex Telles pose a threat going forward and will cause a problem if Rangers cannot threaten them in behind. The latter has a wicked delivery from set pieces and corners, an area where Porto are particularly dangerous and creative.

MIDFIELD

Conceicao tends to line-up his team in a regular 4-4-2 shape with an onus being placed on two wide attacking midfielders in the form of Shoya Nakajima and Otavio. Both must be watched carefully, as their movement will test the likes of James Tavernier and Borna Barisic.

The former, a big summer signing from Qatari football, is a diminutive little technician who plays on the left but favours his right foot while the latter displays pace and direct running off the right and usually finds a good final ball.

That should leave Mateus Uribe of Colombia and Danilo Pereira in the trenches but Rangers will hope that they can get a numerical advantage in there if the likes Scott Arfield and Ryan Kent can funnel back behind the ball in their 4-2-3-1 shape when Porto have the ball yet find space behind those two midfield holders when Rangers have it.

Another wild card who Conceicao could throw into the mix is another international team-mate of Alfredo Morelos in the form of Colombian winger Luis Diaz. Still only 22, this waspish little playmaker is blessed with fast feet and a devilish right foot. He seems set to have a big future in the game.

In general, Porto will look to monopolise possession – they had 61% and 20 shots even in defeat against Feyenoord – and Rangers would be wise to sit in their shape at times and challenge Porto to play through them.

ATTACK

While Porto have goals right through the team, Rangers defenders will have to sit deep or risk ruin from a pair of pacy, strong frontmen in the form of Ze Luis and Moussa Marega. They know all about the former, a Cape Verde international, due to his involvement in last year’s Europa League campaign for Spartak Moscow. A clever player who isn’t afraid to sniff out goals from within the six yard box.

Marega, a Mali international who is also 28, averages pretty much a goal every two games for Porto. A hulking striker perhaps in the form of Romelu Lukaku, his physical gifts make him a handful although he can appear lazy and a touch petulant at times. A danger at set pieces.

To summarise, while will take an excellent performance from Rangers to condense the space to stop Porto's ball players wreaking havoc they can be susceptible at the back to a pacy, counter-attack.