Cameroon coach Hugo Broos slammed the decision to send off Ernest Mabouka in Sunday's 3-1 defeat to Germany as the video assistant referee (VAR) system again came under scrutiny at the Confederations Cup.

Timo Werner netted twice as Germany set up a semi-final clash against Mexico, but Cameroon were seething at the dismissal of Mabouka, who was initially spared after a case of mistaken identity.

The video review system was called upon when Mabouka was sent off on 64 minutes for a dangerous tackle as he went in studs up on Liverpool's Emre Can.

Colombian referee Wilmar Roldan showed Sebastien Siani the red card at first, before his error was rectified and Mabouka received his marching orders instead after intervention from the VAR.

The decision left Cameroon reeling and Germany's Werner scored his first goal just a minute after the dismissal.

"The referee didn't give any explanation," fumed Belgian Broos when asked about the bizarre sequence of events.

"First of all he gave a red card against Siani, then the video ref called him back and told him it was the wrong player, so Mabouka was sent off.

"I think both players (Can and Mabouka) had their legs high, so I don't see why he had to give a red card.

"I think everyone is confused, also me, I didn't know what was happening, I didn't understand it and I still don't understand it now.

"I think this is something for the referee, he and he alone can explain what happened in that incident."

After Kerem Demirbay fired Germany in front just after the break, Werner struck either side of Vincent Aboubakar's consolation effort for Cameroon on 78 minutes.

Cameroon bowed out of the competition after two defeats and a draw, while Germany advanced to the last four as Group B winners.

But Germany boss Joachim Loew also questioned whether the red card was necessary.

"I spoke to Emre Can, he said there was contact but didn't feel it was a foul," said Loew.

"I saw the foul, I didn't have the impression that he had the intention of injuring the player.

"I think we need to get used to the video referee, but it has proven useful with regards to offsides.

"Maybe it can be fine-tuned so that decisions are made a bit quicker."

Two-goal hero Werner conceded the red card played a factor as the 21-year-old struck moments later to double Germany's lead with Cameroon still puzzled by the incident.

"I believe the red card contributed," said Werner. "I didn't see whether or not it was justified, but Cameroon kept attacking even when they were a man down.

"They were courageous, but it meant there was more space for us, so yes, the red card contributed."

Broos also took a swipe at the tournament organisers, demanding team transport at the venues be improved before Russia hosts next year's World Cup.

The Cameroon boss praised the standard of the stadiums in Russia but said heavy traffic hampered training sessions when they played in Moscow and Saint Petersburg.

"On three different occasions we had to start our session an hour late, because we were stuck in traffic, even though we had a police escort from the hotel," said Broos.

"That must be reviewed and sorted out, because in one year's time, when the World Cup is here, teams should not be stuck in traffic.

"It's not that you start an hour late, everything gets pushed back and on one occasion we ate at 10pm at night, which is far too late."