Bayern Munich manager Carlo Ancelotti has said that video technology has become "necessary" after his side succumbed to a 4-2 defeat to Real Madrid in the Champions League.
Arturo Vidal was controversially sent off for two yellow cards, while Cristiano Ronaldo's second goal of the night - which gave Real the lead in extra time - was offside, and it left Bayern to lose by a 6-3 aggregate over the two-legged tie in the quarter-finals.
The officials have come in for widespread criticism since the end of the game, and Ancelotti has claimed that the referee "probably wasn't up to the task".
The 57-year-old is quoted by BBC Sport as saying: "We had thought of everything going into this game - except the referee. You can't decide a semi-final spot like this. It shouldn't happen at this level.
"The referee probably wasn't up to the task. I don't think Real Madrid have any influence on referees. The officials tonight simply got it wrong. I had never been in favour of video technology, but I must admit it's necessary now."
Bayern had led 1-0 and 2-1 in Spain before Real scored three times during extra time.
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