Cristiano Ronaldo did not appear to deserve his red card while making his Champions League debut for Juventus, says Diego Simeone.

Ronaldo was dismissed in the first half of Juve's 2-0 Group H win at Valencia on Tuesday, having clashed with defender Jeison Murillo off the ball.

Replays appeared to indicate Ronaldo pulled Murillo's hair and the former Real Madrid star was inconsolable as he left the Mestalla pitch.

VAR is not yet used in the Champions League, with Juve head coach Massimiliano Allegri calling for the technology to be introduced after Ronaldo's red.

And Atletico Madrid's Simeone suggested he felt Ronaldo - in danger of missing a return to Manchester United through suspension - was unfortunate.

"With VAR, seeing the way in which Ronaldo was sent off, we have to pay attention to what is done," Simeone told a news conference ahead of Saturday's LaLiga trip to Getafe.

"He did not seem to have done anything and was dismissed. The referees have help and that conditions what happens in the field.

"From our place we have to make the game that we believe and we will face a tough team.

"I feel like VAR is always in favour of justice in the game, for sure it will evolve with time.

"My feeling is that it brings more justice to the game than any other thing, of course it can make mistakes and let's hope they will fix them."

Although Atleti won 2-1 away to Monaco in their Champions League Group A opener, Simeone's side have been in poor form in LaLiga.

A haul of just five points from their opening four matches leaves Atletico well off the pace set by leaders and defending champions Barcelona.

And Simeone hinted he could seek to change Atletico's style, his team having kept one clean sheet in six competitive matches this term.

"In the same way that we conceded more goals, in some matches we had the famous possession in favour," Simeone said. "I prefer that we let in fewer goals and have less possession.

"I try to find a way to improve the team, against Eibar we should have won, we deserved a better result, but we did not have the precision to win.

"In my head I have to improve as a team, grow match after match and better see the people who have arrived. Gelson [Martins] did not play, [Nikola] Kalinic almost did not, [Santiago] Arias is injured... The most important are those who have been playing with us for some time.

"[Gelson] arrived recently, he is young and we have to find ways to exploit his characteristics. He is better against rivals who have space, what we are looking for is the right moment. He is increasingly interpreting what the team needs better."