Manchester City manager Pep Guardiola has called for more consistency from English referees, saying he has been surprised by the leniency shown towards aggressive tackling.
City winger Leroy Sane has been ruled out for up to six weeks - and will miss the Carabao Cup final - after suffering ankle ligament damage in Sunday's FA Cup fourth-round win over Cardiff following a challenge from Joe Bennett, who was only booked for the foul.
Guardiola had called for referees to do more to protect players from bad challenges after City's win at Cardiff, while Neil Warnock defended his players, saying it was "part and parcel of the game."
The 47-year-old accepts opposition teams will adopt aggressive tactics against his side but admits he did not expect the referees to be as lenient has they been.
He told Sky Sports News: "I was a little surprised with the referee. It's not just about the physicality. I accept the duels because when people say 'I don't want to accept that' they don't understand anything.
"It's a question for the referees. The players, the teams, can play however they want. When the manager is convinced to be so aggressive with their opponents, it's perfect, but there is one person who has to decide if it is perfect or not.
"We would not have done what we did if you don't accept that challenge. But sometimes I am a little bit surprised in that way [when referees let aggressive challenges go] but I have to adapt to it and I'm sure next season it will be better."
The Spaniard believes the responsibility to ensure player's safety lies with the referees, who need to be consistent with the parameters they set from one week to the next.
Guardiola said: "[Does responsibility lie with the referee?] Definitely. Why one decision is a red card and the other is not, why this is a fault and the other is not - the parameters.
"It's just one guy who has to decide what is the line. When you cross the line something can happen, what happened with Leroy.
"Phil Foden is injured for two months and people didn't think [it was as bad] with the same action [but] they destroyed his ankle.
"We had examples in the past where we were lucky, in the last game [against Cardiff] we were not lucky.
"The measure, what is the level, the referees have to decide. That's why I was sad after the last game, because the referee has to do that. Protect the players, they have to do that."
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