Arsenal boss Arsene Wenger is adamant the Gunners were robbed of a trip to the Champions League quarter-finals by referee Massimo Busacca.Arsenal fell 3-1 at Barcelona in the second leg of their last-16 tie on Tuesday, crashing out of European competition on the losing side of a 4-3 aggregate.But the Gunners will rue Busacca's controversial decision to dismiss striker Robin van Persie in the 56th minute, with scores tied 1-1 and Arsenal ahead 3-2 overall.Barcelona, who were dominant before Van Persie's dismissal, used the man advantage to rack up another two goals through Xavi and Lionel Messi and seal up a trip to the last eight.While conceding Arsenal had been beaten by an excellent side, Wenger was steadfast in his belief that the result would have been different had Van Persie not been dealt with so harshly."We lost against a good team," Wenger told Sky Sports."In the first half we resisted the pressure. I believe that straight away in the second half it would have been very interesting if it had stayed 11 against 11.""But that was not the case and at the end of the day we have many regrets.""We were beaten by a terrific side, certainly the best team in Europe. I am still convinced that in the second half we could have done a lot at 1-1 if it had stayed 11 against 11.""(Busacca) must never have played in games of football of that importance, with people shouting.""Even if he takes the chance, I don't see why it was a second yellow card. He must never have played football at all to do that."Barcelona boss Pep Guardiola admitted Van Persie's dismissal would have been difficult for Arsenal to swallow, but said the Gunners were defeated by a far superior team regardless."Arsenal are a very good team but they didn't make three passes in a row," Guardiola told Sky Sports."So we created many, many chances. We kept a lot of control and played the perfect game, they defended very, very well but they didn't pass more than three or four passes.""I can understand Arsenal's reaction about Robin van Persie, because it's difficult with 10 against 11.""But we are so, so happy with our performance. I think we deserve to be in the quarter-finals. In the two legs we have been better than them."