Jurgen Klopp has refused to entertain the idea that Jose Mourinho has made a poor start to his Manchester United reign.
Mourinho lost three games in a row earlier this season and the Red Devils are currently seventh in the Premier League standings with 13 points.
Klopp, on the other hand, has masterminded a fast start to the campaign at Liverpool, and find themselves three points above United in fourth place.
A win on Monday night at Anfield will see Liverpool claim top spot, relegating Manchester City to second, but Klopp treaded carefully as he prepares for United's visit.
"Who says this [that Mourinho started poorly]?" the German said. "Four people in Liverpool? That's bulls---.
"[Mourinho] has started badly at United? He has won the first how many games? So now you are giving B grades for winning?
"He knows how successful football works. If you like it or don't like the way they play, why should he care? Why should he care?
"He has won the Champions League more often than I played in it. That is how it is. How can I say who is on the way up and who is on the way down? If we lose against Manchester United and we stand here, you ask me, 'What about you?'
"I'm not interested or part of the group that says Jose Mourinho was or has been a good manager."
While Liverpool have earned praise for their attacking football that has seen them garner 18 goals in the league this season, Klopp insisted that securing three points is far more important than playing attractively.
"The way to win it is not top of the list [of priorities]," he said. "It's not showing who plays the better football. We want to win this game.
"We don't just play to enjoy ourselves and say, 'Look it's nice'. We play to win. Of course I want to enjoy our games otherwise I have to wait for the result if there is nothing to enjoy during 90 minutes.
"There is not only one way. There are a lot of different ways and the most successful managers in world football had completely different ways.
"If you think [Pep] Guardiola, [Mauricio] Pochettino, Klopp all have the same way, right, but I know nothing about these guys that I could say is similar.
"From my point of view we have our way without looking left or right. We are only trying to do our best."