One of Argentina's top referees is under investigation and faces a possible ban after overturning a red card and penalty decision based on a television replay. Referee German Delfino awarded a penalty to Velez Sarsfield after  Daniel Valencia was adjudged to have handled the ball in the area and showed the Arsenal man his second booking of the game. However, the decision was overturned after linesman Ivan Nunez caught a replay of the incident on a nearby cameraman's monitor and informed Delfino via his earpiece. One of Argentina's top referees faces a ban after overturning a decision based on a television replay . Arsenal's Daniel Valencia is dismissed by German Delfino after appearing to handle the ball in the area . Linesman Ivan Nunez caught a replay of the incident on a nearby cameraman's monitor and informed Delfino . Delfino overturned the decision  - to the annoyance of Velez who lost out on a penalty and a man advantage . Despite  the correct decision being awarded by the referee - replays showed  striker Mariano Pavone was the handball offender and the frontman was subsequently booked - Velez were left fuming after the penalty was overturned and Valencia was allowed to return to the field. Video technology is not allowed in Argentine football and, after a melee ensued on the pitch involving players and coaching staff, Velez manager Miguel Angel Russo said: 'Delfino has every right to change his decision. But by his own decision, not off the television. 'The Fifa rules are very clear, they don't accept technology... If cameras are to exist then let them be used for everyone.' Velez captain Fabian Cubero gave an on-pitch interview during the game and said: 'You can't change it. What are the rules?' Arsenal's Valencia was allowed to return to the field while Velez striker Mariano Pavone was shown a yellow . Velez players and coaching staff protest at referee Delfino after his decision to overturn the decision . Velez manager Miguel Angel Russo said: 'Delfino has every right to change his decision. But by his own decision, not off the television' Velez captain Fabian Cubero gave an on-pitch interview and said: 'You can't change it. What are the rules?' Meanwhile, referee Delfino accepted the decision was sloppy and admitted: 'The procedure was horrible. It can't happen like this. 'You've got to be strong. I changed the decision because of my colleague, we are a team. 'If it was handball by Pavone then I'm happy that there was justice... but it was sloppy and I'm responsible.' After his initial reprieve, Arsenal's Valencia picked up another booking and was dismissed deep into injury time as Velez went on to claim a 2-1 victory.
German Delfino faces ban after overturning decision based on TV replay . Linesman Ivan Nunez spotted replay of incident in cameraman's monitor . Argentine referee Delfino overturned penalty and red card decision . Velez Sarsfield were left furious after decision during game with Arsenal .