Frankfurt - An experiment using "goal referees" has received a mixed response following its premiere in football's newly-launched Europa League.
"It promised to be UEFA's version of a nuclear test, but Thursday night's experiment with officials behind the goal turned out to be more like third-formers messing around with litmus paper," Britain's Mirror daily reported on Friday.
There was a good measure of amusement and annoyance among coaches and players after the first night of the extra-refs project.
"You just have two more people standing around doing nothing," was Rapid Vienna coach Peter Pacult's judgement - with a good portion of Viennese humour - after his side had humbled German league leaders SV Hamburg 3-0.
"I don't think though that the game will suffer additionally by having two more penguins running around on the pitch," he added.
The referees themselves might have something to say about that, but the officials - according to Knut Kircher, Germany's only refin action on the night - have been told not to make any comments,
"We have been given a muzzle," he told German Press Agency dpa.
"We got an extra mail from UEFA telling us we aren't allowed to say anything about the experiment."
Hamburg coach Bruno Labbadia seemed to agree with the adage that if you have not noticed the referee he has had a good game.
"They weren't noticed so they were good," he said of the extra officials in the Ernst Happel Stadium.
However, he may have overlooked a sign that the system worked to his side's benefit. When Hamburg defender Jerome Boateng handled the ball in the area in the 41st minute Croatian referee Ivan Bebek decided against a penalty after receiving a message on his headset from the "goal ref" that it was unintentional.
In UEFA's experiment, six match officials are working together in all 144 matches in the Europa League's group phase.
The usual four-man team of referee, two assistant refs and fourth official are supplemented with the two additional assistant refs standing alongside each goal.
The assistants, who don't have flags but use a radio communication system, generally remain behind the goal line, but if they want to keep up with play may enter the penalty area when play moves towards the other end of the pitch.
The Mirror seemed less than impressed by it all.
"Excitable fans who had pictured the extra men scampering about behind the goal to look for shirt-pulling and set-piece blocking will have been disappointed," it said.
"They mostly stood stock-still, arms folded behind them, on a diagonal a couple of yards away from the right-hand post - although a few, as they are allowed to do, ventured onto the pitch when play was up at the other end."
Members of German side Werder Bremen also appeared unconvinced after a 3-2 win at Portuguese side Nacional.
"In principle having six referees isn't a bad idea but then they have to see things like a clear penalty," striker Aaron Hunt said after he felt he had been clearly fouled in the area.
Goalkeeper Tim Wiese said: "Before the match I thought it made sense but after today's impression I think it's probably superfluous."
Werder sports director Klaus Allofs had been sceptical beforehand, saying: "If we have five different opinions it's going to get complicated."
German ref Kircher, who was in charge of the Benfica-BATE Borisov game in Lisbon, meanwhile got good marks for his performance from the Correio da Manha newspaper but his assistants were criticised for missing a foul and a handball in the penalty area respectively.
"A good ref who was poorly supported," it said.
It's clear the experiment will need time for acceptance for all concerned, not least the players.
"It's a bit unusual when you suddenly have five referees standing in front of you and you have to shake all their hands," said Hertha Berlin defender Arne Friedrich of his pre-kick-off experience.
DPA