Slot's incredible start to life at Anfield continued with a 2-0 win over Real Madrid on Wednesday to move back to the top of the Champions League table.
Liverpool are also streaking clear at the top of the Premier League, eight points ahead of City, who are suffering the worst run of form in Guardiola's managerial career.
After five consecutive defeats, City collapsed from 3-0 up in the final 15 minutes to draw 3-3 against Feyenoord in midweek.
The loss of Ballon d'Or winner Rodri to a season-ending knee injury has been a colossal blow to City's chances of defending their title.
Slot is confident Guardiola will turn their fortunes around, but is hoping it will not come in time for the top-of-the-table clash.
"One of the reasons why I think Guardiola is the best manager in the world is that he always comes up with solutions for his problems," Slot said at his pre-match press conference on Thursday.
"His problem now might be that Rodrigo is out, but we all know, I think, that he will come up with a solution and the run of form will go again. Hopefully after Sunday.
"I think he was the one who started playing the inverted full-back, then he was the one that started to play the centre-back as a number six. So I don't think it's a surprise for anyone if he again comes up with something no-one has ever thought about before to make his team even stronger."
Liverpool's latest statement win, to defeat Madrid for the first time in nine meetings, came at a cost.
Defenders Conor Bradley and Ibrahima Konate are doubtful for the weekend after suffering injuries late in the game.
"It's never a good sign if, in Conor's case, we had to take him off and Ibou couldn't walk off the pitch as he should after such a fantastic game that he played," added Slot.
However, the Dutchman confirmed Trent Alexander-Arnold would be fit enough to replace Bradley if necessary.
All three previous sides to enjoy at least an eight-point lead after 12 Premier League matches went on to win the title.
Liverpool have won the league just once since 1990 and have missed out twice in recent seasons to City by a single point as Guardiola's men have racked up six of the last seven titles.
Slot refused to buy into the idea that the defending champions are there for the taking when asked if City's slump has made Liverpool's task easier in the title race.
"I don't think anyone in the last eight or nine years, or maybe even longer, would have said that City, home or away, that the word easy ever comes to mind."
