Guardiola's Manchester City side won the Premier League title last season with a record points tally of 100 - however, the Spaniard was full of praise for the impact Klopp has had at Anfield recently.
Aguero and van Dijk are key to both City and Liverpool's hopes on Sunday and they have each started their respective season in fine form, with the Argentina worldwide already with eight goal scoring contributions to his name and the Dutch defender with four clean sheets. "In the Premier League we beat them, in the Champions League we didn't". He has transformed them into a title-challenging team year in, year out.
"We beat City three times last season and not once after any of those games did we go into the dressing room and think "now we know how to beat them". They were better than us, in my opinion. Guardiola said. "We try to be close to them. We hope we can finish that (unbeaten) run".
City's wins over Newcastle, Fulham, Cardiff and Brighton put Guardiola in contention for his sixth monthly award, but he faces competition from Jurgen Klopp (Liverpool), Nuno Espirito Santo (Wolves) and Unai Emery (Arsenal).
The pair's fierce but amicable rivalry stretches back to 2013 when Guardiola was in charge at Bayern Munich and Klopp was at Borussia Dortmund.
That's the view of former Manchester United defender Gary Neville, who says he was surprised to see the Reds front three play for as long as they did against Napoli on Wednesday. "He is an excellent manager, I have a lot of respect for the way he plays, his proactive teams".
He said: "After the game it felt much more clear they deserved to win than after the analysis".
"It was a tough one and it was hard to take, but they're the type of lessons you learn from the most". Roberto Firmino and Sadio Mane will as usual complete the attack.
'After today's game we have two weeks, then we go straight into games against Chelsea, in the Premier League, and Juventus, in the Champions League, with two recovery days in between, ' Mourinho said in his matchday programme notes ahead of the game against Newcastle at Old Trafford.