Fabianski - deputising for the injured Manuel Almunia - had an evening to forget at Estadio do Dragao on Wednesday night, as his costly errors saw the Gunners suffer a controversial 2-1 defeat which leaves their hopes of making it to the quarter-finals of the Champions League hanging in the balance. Manager Arsene Wenger had spoken of his complete confidence in the "massive potential" of the young Pole in the build up to the first leg of the last 16 tie. However, Fabianski - who was less than impressive in last season's FA Cup semi-final at Wembley and then found himself exposed in the fourth-round defeat at Stoke last month - was once again unconvincing. First, the 24-year-old pushed Silvestre Varela's cross into his own net before then giving away a free-kick when he picked up a back-pass from Sol Campbell which led to Porto's second goal. Fabregas, though, insisted the whole dressing room was behind the keeper, who looks set to be between the posts again for the visit of Sunderland on Saturday. "He is a very good keeper," said the Arsenal captain. "He had his chance and sometimes it doesn't go your way. "But we will stand up and support him until the end because he is a good character and I am sure he will be back." Fabregas added: "Lukasz is strong and we have to be there for him. Sometimes when you are young in a big game, these things happen to you." The Arsenal captain, however, was less than impressed by the "schoolboy" defending which cost his side against the Portuguese champions. Fabregas warned such lapses in concentration must be eliminated if the Gunners are to avoid another barren campaign. "Sometimes we make mistakes which, at the top level, you pay for," he said. "It happened against Chelsea and Manchester United, now again in Porto, so I think we have to try to find the solution to these problems because it is costing us many, many things. "The other top teams do not make these mistakes as often as we do. "We can only change it by working and training I guess." One positive from the defeat was what could yet prove to be a crucial away goal from veteran Sol Campbell, whose headed equaliser was his first back in Arsenal colours since the Champions League final against Barcelona in 2006. Porto were beaten 4-0 on their last visit to the Emirates Stadium during September 2008, and lost twice to Chelsea in the group stages earlier this season. Arsenal, however, have not overturned a first leg deficit in Europe since the 1978-79 campaign, and were hit by a late goal from Brazil defender Alex when PSV Eindhoven secured a 1-1 draw at the Emirates Stadium three seasons ago having been 1-0 up from the game in Holland. Fabregas, though, maintains the Gunners can fight their way through to the last eight. "It is going to be hard for us in the second leg, but I am still confident we will prevail in the end," the Spain midfielder said. "We will just have to see who is strongest on the night." Fabregas added: "We knew Porto had a very quick and talented team, but the truth is we allowed them to score two very easy goals. "You just can't let that happen at this level. Now we are 2-1 down and we are going to have to fight our way back."
