The England worldwide set-up Sadio Mane with a perfectly weighted clipped ball in the second half, but the goal was rightly ruled out for offside.
"I'm happy, it's the first game ahead of an intense second leg", Klopp said.
"But titles are not always won and lost against the teams that you think". With the confidence of having eliminated Bayern Munich in the round of 16, it carried over for Jurgen Klopp's men, who played freely, confidently and defended well in numbers against a team that was able to eliminate Roma last time out.
Henderson added: "Obviously we wanted to come out in the second half and score one or two more if we could, but that wasn't the case". It should prove enough for Liverpool to claim their place in the last four in what is turning out to be a fascinating season for the club. His forward passing was a joy to behold, and he didn't neglect his defensive duties, constantly tracking back in another energetic and thrilling showing.
Chelsea's Eden Hazard celebrates after scoring the second goal against West Ham United, April 8, 2019.
James Milner and Sadio Mane were involved in the buildup to find Firmino inside the area, and the Brazilian then teed up an unmarked Keita on the edge of the box.
Keita then teed up Salah for a left-foot volley which was saved by the former Real Madrid goalkeeper, who was subsequently beaten by the Egyptian's gentle shot from an errant backpass which rolled past the post. 2-0 is a really, really good result.
Just five minutes later and it was two though, with skipper Jordan Henderson the architect of a brilliantly simple team goal.
Porto though showed it was not about to roll over - the unsafe Marega had a low drive well saved by the legs of Liverpool keeper Alisson Becker. Mane seconds him on the leaderboard, while it's Andy Robertson who has been the main creator of goals for others with nine on the board up to now, two more than right-back Trent Alexander-Arnold and Salah.
The visitors also felt they should have had a penalty when the ball struck Alexander-Arnold's arm as he shepherded it out but after a VAR review the appeal was rejected.