The French full-back moved to City from Monaco for a fee of £52 million last summer but missed the majority of his debut season in England with a cruciate ligament injury.
City have not beaten the Reds at Anfield in any competition since May 2003 and have lost on their last six league visits.
"They [players] know that they have to be here on time".
"But they should be here and he knows it".
City would go on to be runaway Premier League champions, while Liverpool would lose in the Champions League final, but - thanks to the football served up by Guardiola and Klopp - their clashes were among the highlights of the campaign.
Still, City won well enough to be able to look forward to Sunday's big game at Anfield with optimism. "Sometimes he does little insane things but he's a good guy and we hope he can come back as early as possible to help the team".
Pep Guardiola's side have scored eight goals in their last two games, without conceding once, and will be eyeing another comfortable win against the Seagulls.
"Now it's Hoffenheim, and after that we are going to prepare, and after that we're going to prepare for Burnley".
City's thoughts will now turn to Tuesday night in Germany where they will have to bounce back from a defeat against Lyon in their opening European fixture.
Pep Guardiola also heaped praise on Oleksandr Zinchenko after the Ukrainian turned in his second impressive display inside five days.
Meanwhile, Brighton sits in the crowded bottom half of the standings and has just one win on the season, earning just two points over its last four matches.
"Leroy was important, is important, and will be important for us, but our profession is so demanding, and we have to do every single day your best and of course in the last two or three games he was really good".