A call from the video assistant referee (VAR) to award a penalty during the half-time break in a Bundesliga match has sparked more controversy in Germany.

Mainz's 2-0 home win against Freiburg on Monday night became controversial after the players were ordered to return from their dressing rooms for the penalty to be taken.

"It was very strange, we were already sitting in the dressing room. We couldn't believe it at first," said Freiburg goalkeeper Alexander Schwolow.

The VAR system will be used at a World Cup finals for the first time in Russia this June.

However, the incident in Mainz is just the latest in a series of controversial scenarios which VAR has caused this season in Germany, where the system is being trialled.

Late in the first-half in Mainz, the hosts had appeals for handball turned down by referee Guido Winkmann with the match goalless.

The ref blew for the half-time break and the teams left the pitch for their dressing rooms.

However, after a delay of several minutes, the game's video ref Bibiana Steinhaus, who was in the VAR centre in Cologne, confirmed to Winkmann there had been a handball.

The players were called back and Mainz forward Pablo De Blasis drilled the spot-kick past Schwolow.

"I was not aware at the time that there was a handball, but when I later saw the images myself, it definitely was," said Winkmann.

"We played through just such a scenario on a pre-season course.

"Of course, something like this is unusual, and I wouldn't be happy about it as one of the clubs involved.

"A half-time whistle only interrupts the game, the final whistle finishes it and such a decision would not have been possible."

The head of the VAR in Germany admitted the curious incident was not ideal.

"These are scenes that nobody wants," Lutz Michael Froehlich told Eurosport.

"This is not a good advert, but in this case it was not possible to do anything else.

"The referee did not notice the situation in the game at all, that's why the VAR ref took care of it.

"In the end, the whole process was correct, but it runs counter to the basic idea of spontaneity and emotion."

Even Mainz coach Sandro Schwarz admitted the timing of the penalty decision was not good.

"I think that the decision was absolutely correct. I sat in the dressing room and saw the replay," he said.

"The timing was, of course, very unfortunate for everyone."

Former Germany international Matthias Sammer said it cut against the spirit of the game.

"There is a lot of basis here for discussion. I have not experienced anything like that before," said the former sports director of the German FA.

"In the rules, it's debatable.

"I have a hard time seeing whether there is a clear wrong decision here - it's not one in my eyes.

"I don't see the need for intervention and I'm more interested in the soul of the game."