Andoni Iraola says that he will tell his players to go down in future after Liverpool were denied a penalty in Sunday’s defeat by Arsenal.

With Liverpool trailing 1-0 after Kai Havertz’s opener, Alexander Isak’s shirt was pulled by Jurrien Timber in the first half as he went for a header from Bradley Barcola’s cross.

However, the Liverpool striker stayed on his feet and referee Andy Madley did not point to the spot.

Stuart Attwell, on video assistant referee (VAR) duty, determined that there was not enough in the tug for the decision to be overturned, but Iraola disagreed.

“There is a clear grab of the shirt,” the Spaniard told Match of the Day. “Alex [Isak] was just in front of him, he was going to head in front of the goal but couldn’t because he grabbed the shirt.

“If he goes to the floor, they call the penalty 100%. It should be like this but it is what it is. Next time, the managers should tell Alex to go to the floor, otherwise they won’t call it.”

On what the answer is going forward, Iraola added: “The answer is you have to dive, if you don’t dive they won’t call it.”

Isak turned and spoke to Timber after the incident, but did not appeal to the referee after staying on his feet.

Iraola told Sky Sports that going forward, managers should tell their players to go to the floor.

On if he will tell Isak that going forward, he added: “Yes, definitely.”

He elaborated in his news conference when asked by BBC Sport if he would have to tell his players to be more smart, going forward.

“It’s a shame you ask me this question, but honestly, yes, we have to tell them, go down, because they’re not going to call it otherwise. And then referees complain why they go down. Because if you don’t go down, you don’t call it. Then it’s like, no, you are all the time going down,” said Iraola.

“But I think Alex is honest. He tries to go for the ball, everyone can see live straight away that there is a clear, clear pull.”

The understanding is that because there was minimal contact and it was a slight tug on the shirt, rather than a sustained holding offence, the play was allowed to continue.

Iraola conceded in his news conference that “it is not going to change anything” if Pro Ref, the Premier League’s refereeing body, was to offer an apology about the incident.

Former Premier League assistant referee Darren Cann told BBC Sport: “Timber takes a huge risk by grabbing the shirt. It could easily have been given on another day.

“It’s right on the limit. It has to be sustained holding – some will say it was sustained, some will say it wasn’t. But it’s interesting that Isak didn’t even appeal.”

Liverpool also had another penalty appeal turned waved away when Cody Gakpo went down in the box under pressure from Christos Tzolis.