Arsenal manager Arsene Wenger accepted his side were ' a bit lucky ' after a fumble from Reading goalkeeper Adam Federici handed them a 2-1 extra-time victory and a place in the FA Cup final . The Gunners will head back to Wembley on May 30 aiming to defend the trophy after edging past the Sky Bet Championship side , who had rallied after going behind just before half-time to a fine goal from Alexis Sanchez . Reading drew level on 54 minutes when Garath McCleary 's volley was deflected past goalkeeper Wojciech Szczesny , who could only palm the ball back over the line . Arsenal manager Arsene Wenger accepted his side were ' a bit lucky ' to beat Reading on Saturday . Wenger 's side failed to hit the level seen in recent games against Reading at Wembley . Although Arsenal did twice hit the woodwork through a header from defender Gabriel , which was touched onto the crossbar by Federici at full stretch , and a close-range shot by Aaron Ramsey , the Barclays Premier League side could not find a winner in normal time . In the end , an error from Australian Federici proved so costly , the keeper allowing a low , angled shot from Sanchez to slip through his legs and roll over the line on 115 minutes . 'It was a difficult game against a well organised , resilient , committed and physically strong Reading team , ' Wenger said . 'They really wanted it Reading , they were willing to die on the pitch to go to the final and you have to congratulate them for the effort they put in . 'In the end , we were a bit lucky because their keeper made a mistake and I can understand that he is distraught , but as well he kept them in the game for long periods . ' Wenger added : 'What was missing was a bit of speed of combination and sharpness in the final third maybe , but overall the concentration was there . Alexis Sanchez 's low shot squirmed agonisingly through the legs of Reading goalkeeper Adam Federici in extra time . It was a routine shot from Sanchez but the Reading stopper failed to collect it properly in his grasp - an embarrassing gaffe . The ball rolled through his legs and slowly towards the goal line in the 106th minute of the game . Federici tries desperately to stop the ball going over the line after it rolled through his legs and out of his grasp . ' I do n't think we switched off ( for the goal ) , but after half-time we did not come on with the same intensity . We started to suffer and we paid for that . ' Wenger refused to single out Szczesny for blame on the Reading goal . ' I would have to see it again , ' he said . 'At first I thought it was not in because it took some time for the referee to give the goal , so I thought 'okay , we escaped ' . Federici lies slumped on the ground as the impact of his error hits him in the FA Cup semi-final against Arsenal . 'But on slow motion maybe he goes back a bit to save the ball with his feet , then when the ball bounces , it was certainly over the line . 'We will have to analyse it , but the cross should not have come in and after the guy was free , so it was a combination of mistakes . ' Wenger said an ankle injury to defender Per Mertesacker 'does not look good ' , which could make the German defender a doubt for Sunday 's Barclays Premier League game against leaders Chelsea at the Emirates Stadium . The Reading goalkeeper , who had been magnificent until then , left the field in tears as manager Steve Clarke tries to console him . Arsenal reached a record 19th FA Cup final , and will be looking to overtake Manchester United 's mark of 11 victories , with five coming under Wenger 's tenure . 'Now , let 's focus on our next game , we come back here in the final , but we have time to prepare , ' Wenger said . 'The final is a 50-50 ( game ) . If we can beat the record we will be very happy . 'Let 's hope we have all of our players available and come back in good shape . ' Federici 's opposite number , Wojciech Szczesny ( left ) of Arsenal comforts his fellow goalkeeper after the game is resolved . Chelsea look in a strong position to go on and win the title , having defeated United 1-0 at Stamford Bridge on Saturday evening . Wenger said he was unaware of the final result when quizzed on its significance at the post-match press conference . ' I ignore completely what happened . Chelsea won 1-0 ? The usual , ' the Arsenal boss said . 'We will see next week . '
Arsenal reached the FA Cup final despite failing to live up to recent form . Reading gaffe was only difference between the sides at Wembley . He let a soft Alexis Sanchez effort squirm through his grasp in extra time . Wenger felt Federici kept Adam Federici 's in the game with numerous top saves .