Liverpool boss Andoni Iraola says he was angry about being prevented from making a triple substitution sooner during Saturday's 2-2 Premier League draw against Nottingham Forest.
With the game level at 1-1 during the second half at Anfield, the Basque wanted to bring on Ryan Gravenberch, Kostas Tsimikas and Rio Ngumoha.
However, despite the ball going out of play three times, the players were left waiting on the sideline as fourth official Tim Robinson had problems with the board.
To add to Liverpool's frustrations, the third time the ball went out, instead of play stopping for the changes, Forest took a quick throw-in from which they won a penalty to retake the lead.
Forest wing-back Neco Williams darted in behind the Liverpool backline and was caught by goalkeeper Alisson as he lifted a shot goalwards.
When it drifted wide, referee Samuel Barrott blew his whistle and pointed to the spot.
"With the penalty, the situation has already finished when the contact appears. And it's not an aggressive contact," Iraola told BBC Match of the Day.
"But more than this, we complained about the subs. We had to wait about three minutes.
"He was having an issue with the board; I don't know if it was not working, but we definitely wanted to do the subs the last two or three stoppages before the goal.
"It wasn't just that reason, but everything helps."
Speaking to TNT Sports, he added: "A professional fourth official cannot take three minutes. We'd already given him the subs two or three minutes before.
"I was already angry because in the previous stoppage we couldn't make the subs and then before throw-in I thought we could do it.
"I don't know, they will have to explain it. But it has taken ages."
- 'Appalling from the fourth official'
Former Liverpool captain Steven Gerrard believed they could have no complaints over the award of the penalty itself but empathised with Iraola's anger over the substitutes.
"You can understand the frustration - in this day and age, with all the technology, it can't be taking three minutes to make a triple substitution," he told TNT Sports.
"But I think it's a small problem in the overall problem because it's a goal that can be avoided."
Ex-Liverpool and England full-back Stephen Warnock agreed with his old team-mate.
"Andoni Iraola wanted to make a triple change and the assistant referee hasn't got the thing done," he told BBC Radio 5 Live.
"It would've completely stopped the play. It's appalling from the fourth official."
Liverpool were able to salvage a point from the game as Victor Munoz scored his first goal for the club with eight minutes remaining.



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