The pair have covered at right-back in the absence of England international Nathaniel Clyne, who has not featured this season after suffering a back injury.
Gomez, who signed for Liverpool from Charlton Athletic, has been favoured for the Reds' domestic matches while 19-year-old Alexander-Arnold has been selected by Klopp for the Champions League group stage games.
"Joe and Trent have done really well," Klopp told the club's official website. "They have improved a lot, both of them in different games. That's why we don't have to put pressure on [Clyne] in this situation.
"It's fantastic and good for them that they don't each have to play all the games because it would not be possible. Maybe for Joe a little more than Trent, but even for Joe it's good that he doesn't have to play all the games like this.
"A normal rhythm is good for a footballer with one game a week. So far the way they have performed in this position is a big help for all of us."
Liverpool face West Ham United at the London Stadium on Saturday, with Hammers boss Slaven Bilic under pressure after a poor run of form.