The Reds take on familiar opponents in the Portuguese champions, having thrashed them 5-0 in the last-16 of last year's competition.
Liverpool left-back Andy Robertson will be serving a one-match suspension after picking up his third yellow card of the competition against Bayern last time around, giving Klopp a slight conundrum to solve.
The Reds should be in confident mood after their exploits this season, although Klopp has warned his side to keep their composure against a "really difficult" opponent.
Porto are a physical and dynamic side who are more than capable of hurting the Reds and the onus will be on Liverpool to put some distance between the two before the away leg.
Here's how we think Liverpool will line up on Tuesday night...
Robertson's suspension is a blow for Liverpool, with the left-back pivotal in closing down space on the left and equally integral to the Reds' attacking play.
Klopp could have had the option to turn to Gomez should he have returned against Southampton as originally intended, however the youngster needs more time in training.
“We wanted to have Joe around, not because he is now 100 per cent ready but it was just nice to have him,” Klopp said of Gomez's availability.
“He could be maybe [available] but for him it's better to have more sessions. Joe needs that, he is not long enough in training.
“If we don't struggle players-wise, that we don't have enough, then we should not think about Joe for the next one or two weeks because now he needs really proper training. He was around, that was good.”
Virgil van Dijk is fit despite suffering a knock from "a fall on the ground" on Friday, and the Dutchman is set to feature alongside Joel Matip, Trent Alexander-Arnold and Alisson in the Reds back-line.
Alisson, Alexander-Arnold, Matip, Van Dijk, Milner
Oxlade-Chamberlain is unlikely to feature, however he could yet be a surprise inclusion on the substitutes bench.
Gini Wijnaldum suffered a back problem against Southampton however Klopp confirmed during his pre-match press conference that the midfielder is expected to be in contention for the game.
Jordan Henderson will be vying for a starting role after making a huge impact off the bench against Ralph Hasenhuttl's side, including an assist for Mohamed Salah and a goal of his own to seal a 3-1 victory.
Wijnaldum has looked somewhat fatigued in recent weeks - and it's no surprise considering he has 13 more appearances than any other Reds midfielder this season - but it's likely that Klopp will stick with the Dutchman for a fixture of this magnitude.
It means Naby Keita is most likely to make way for Henderson, despite scoring his first ever Liverpool goal against Saints.
Fabinho is almost certain to be needed against Porto's physical style of play and it is unlikely Klopp would leave out the Brazilian, although Milner is another possible option should Moreno fill in at left-back.
Fabinho, Henderson, Wijnaldum
Mohamed Salah scored his first goal in nine games for Liverpool as he netted the Reds' crucial second against Southampton and reached the milestone of 50 Premier League goals for Liverpool.
The Egyptian will now be looking to build on that goal and strike his 15th Champions League goal in just 24 appearances for the Reds on Tuesday.
Sadio Mane has scored three goals in Europe so far this season - the same as Salah - and the Senegalese will undoubtedly join him and Roberto Firmino in attack.