Fellow right-back Trent Alexander-Arnold has come in for the former Charlton man in the last couple of games for Klopp's side and the local boy looks set to retain his place on Sunday.
The Liverpool boss said he believes Gomez could be back for Porto, however Sunday may be too far for the youngster.
“He was running outside but not with the team but that means he’s close," Klopp said.
“I don’t think he has a chance for Sunday if they don’t come in and say the running was the good! We can have him this afternoon as well but then Porto, there’s a chance. We will see."
The boss also provided an update on duo Ragnar Klavan and Alberto Moreno, who both look on course to make a return in due course.
“Raggy (Klavan) trained the last two days. Alberto (Moreno) needed only two days again and looked good yesterday. That’s it – nothing else at the moment." Klopp said.
“I’m not 100 per cent sure with Clyney, [he] is still not in team training but he is as close [as he has been] since the summer,” the German told reporters.
“He’s on a really good way, close to being back in team training but, how you can imagine, when you are that long out then it will probably take quite a while to be ready to play.”
“I think we need to at least go one round further so that Clyney can be involved, there’s no chance for him in the next round against Porto. So I hope he will make an impact.”
Jürgen Klopp used several of his first team players to try and build up their match fitness during the U23 tie, with Ben Woodburn, Danny Ings and Dominic Solanke all playing alongside England international Lallana.
Klopp says the midfielder could be in the squad for the trip to the south coast to play against the team he captained.
“It’s not nice. I spoke to him about that. It’s not how it should be. He wasn’t happy about the reaction and I wasn’t either," Klopp said.
“He’s an option for the squad. Maybe not the first XI. He looks fresh and good but we need to settle a bit and use Adam as there are about 18-19 games to go.”