Liverpool manager Jurgen Klopp defended Pep Guardiola, saying the Manchester City boss was having to deal with a weaker squad and a more competitive Premier League.
Guardiola's only hope of a trophy in his first season at City appears to be the FA Cup after his side's last-16 exit in the Champions League.
The former Barcelona and Bayern Munich coach arrived in England on the back of trophy-laden stints in Spain and Germany.
But Klopp, whose team visit City on Sunday, said the players at Guardiola's disposal were far different, having been in charge of modern-day greats at Barca, and it made it especially difficult in Europe.
"We really have to compare the squads," Klopp said, via The Independent.
"A team without [Lionel] Messi or with Messi? Come on. A team with [Andres] Iniesta or without Iniesta? A team with Xavi at his best or without? That's the difference.
"You can't compare one with the other. You can see what he wants. That is probably the most important thing if you judge a manager."
City are third in the Premier League, but they are a distant 10 points behind runaway leaders Chelsea.
Klopp also believes a more competitive competition has made it trickier for Guardiola, who won three consecutive league titles at both Barca and Bayern.
"Could he have won a few games more? Yes. Thank God they didn't so obviously we are still around them," the German said.
"It's the same situation we had. We played a few outstanding games, but we obviously get judged by the games where we are not very good.
"We work really hard on it all week to bring this on the pitch but I'm sure he does the same. In England it's the difficulty of this league and the quality of the players around.
"In Spain there's always Madrid, and I don't know, Valencia had a good year, Sevilla, Atletico of course, all that stuff. But the rest are not as good or not good enough to challenge Barcelona."