17th September 2007 The Daily Mail
Liverpool have become a formidable side in Europe under Rafael Benitez, but in Porto they face a team on top domestically and in good form.
Here we assess the key individual battles.
RICARDO QUARESMA v STEVE FINNAN
One of the most high-profile players in Portugal, Quaresma has consistently been linked to the likes of Chelsea, Real Madrid, Bayern Munich and Liverpool themselves.
He is naturally skilful on the ball, possesses speed and trickery that have drawn comparisons with Cristiano Ronaldo and has experience of playing at the highest level with Barcelona.
Finnan, meanwhile, is the unsung hero of Liverpool's back four. Quiet and unspectacular, he nevertheless has a huge work-rate and supports the attack competently.
He faces as stiff a challenge as any of his team-mates in this tie.
LISANDRO LOPEZ v JAMIE CARRAGHER
Carragher's decision to call time on his international career means he will be even more intent on shining on the big stage for his club.
He will be well rested after sitting out England's recent Euro 2008 qualifiers and keen on reproducing the form which has made him one of the most consistent defenders in the Champions League during Liverpool's outstanding recent record in the competition.
Lopez is an Argentina international with an eye for goal and he caused Rangers no end of problems in scoring twice agains them in 2005/06.
He will tax Carragher but the Reds centre-half will fancy his chances of a shut-out.
PEDRO EMANUEL v FERNANDO TORRES
With inspirational captain Steve Gerrard still suffering from the hangover of his fractured toe, Liverpool's attacking onus will be firmly on record signing Torres.
He was rested at the weekend but again looked lively when he was called on from the bench.
His deftness of touch and speed through the penalty area are both big assets as is the Spaniard's vast experience of continental football.
Emanuel has been a solid performer for his club since 2002 and captains with passion. He will need more than that, though, if he is to silence the lively Torres.